SNES - The graphics look really great all things considered, obviously it's been downgraded from the arcade version somewhat but it still retains the look very well with pretty good textures, a lot of environment details like barrels, bucket's and trough's and pretty excellent water effects (especially the river in the 1st level which looks very high quality) One issue I do feel is worth mentioning though is that many aspects of the graphics have been sanitized, the women are now wearing long dresses instead of the questionable attire they had on before, the American Indians have been removed and replaced with the generic cowboy sprites, and your character is no longer set on fire and burned to death.

Mega Drive - The view has changed from being a little to the side to being straight on. When just looking at the base detail and effects what we have is very uneven, some of the levels have an awful lot of effort put into them and actually have better detail than in the SNES version, an example would be the 2nd stage on the train which has a helluva lot more detail in the backgrounds and superior parallax (there's even foreground parallax going on with cacti) on the other hand some other stages such as the Indian level are so scrappy that they look unfinished with poor textures, fuzzy sprites and generally graphical elements that don't blend into each other as they should. The last important thing worth mentioning is that the textures are definately worse here, much of the time there isn't really any ground texture at all and the wood texture for the houses and such is noticibly cruder.

SNES - Very impressive, loads of colours being used and the colour choices look relatively close to those in the arcade version too.

Mega Drive - It's not bad, but there's an instantly noticible drop in the number of colours being used onscreen compared to the SNES version, and the colours that are there don't fit as well (The skin colour isn't quite skin coloured, the wood colour isn't quite wood coloured etc)

SNES - Pretty good animation across the board, the standing animations are especially noteworthy as they contain a lot of frames and different actions.

Mega Drive - Acceptable animation, the walking looks a little stiffer here, and generally there's fewer frames and details going on (for instance the gun doesn't recoil when you shoot like it does in the SNES version) Standing animations are much worse than before as half the actions have been cut.

SNES - Very smooth scrolling

Mega Drive - Very smooth scrolling, more layers of parallax.

SNES - Very high quality tunes that fit the theme of the game well, many of which are quite catchy.

Mega Drive - Like the SNES version but in slightly lower quality.

SNES - Good FX and Loads of fairly impressive voice samples.

Mega Drive - The sound effects here are worse pretty much across the board (even the gunfire doesn't sound much like gunfire any more) but saying that they still do an acceptable job. The voice samples for all the bosses are sadly missing, there is however one new sample "thank you nice boys" spoken by the women after they are rescued at the end of each 1st stage, which is pretty cool.

Sunset Riders plays like your average Contra style run n' gun game with the high jump from Rolling Thunder/Shinobi added on, it has you moving through a wild west setting shooting the enemies and collecting weapons power-ups which either give you a second gun or the ability to rapid fire. One of the more notable aspects of the original was the fact that it had a 4-player co-op which was quite rare for the time (the 4-player mode is missing from both ports).

SNES - The gameplay is relatively accurate here apart from sadly missing the 4-player co-op and the fact that it's generally more difficult mainly due to the unfortunate fact that you get put back to the start of the level when you use a continue, which I actually take quite an exception to as dying on a boss only to be put back to the start is frustrating as hell and doing each level with 3 lives can be tough, thankfully however this does not happen in 2-player mode. The biggest exception to accuracy within the levels is probably Level 5 which as mentioned earlier has replaced the American Indians with the generic cowboys (the Indians actually had different moves so this changes the gameplay of that stage somewhat).

Mega Drive - Only half the arcade levels were converted here but the levels that were are lengthened and split into two stages each (Basically the level progression goes Level 1 -> Level 4 -> Level 5 -> Original Level) The last level has been completely replaced by a new level where you're storming the mansion in the rain being attacked by dogs, a level which is pretty good but doesn't really do anything new. These changes to the level progression have the effect of making the game pretty much the same length as the SNES version but much more lacking in variation. The last drastic change has been made with the boss of the train stage as El Greco has been replaced with Paco Loco (The boss from arcade/SNES level 6) Paco's moves don't fit in well with the new environment. On the other hand though the Indian level here (SNES level 5) is actually much more accurate to the arcade than the SNES version as it retains the indians who fire flame arrows (the SNES version replaces them with normal cowboys) it's bridge section drops as you walk across it, and there's also a lift section which was replaced in the SNES version by a hand over hand rope section.

Bullets travel faster here making them much harder to dodge which unfortunately makes this version cheaper and less fair as it's more based around trial and error now. The bonus stage where you have to shoot as many enemies as possible has been replaced by a horseback riding stage where you have to catch items being thrown by a carriage, the new bonus stage is fairly fun to play, I'd say that though very different it's still pretty much as fun as the original. Some other noteworthy aspects are that you now have a stand still and aim ability which is very helpfull in certain situations and is definately a good addition (as it means you can fire diagonally without walking in that direction), and shooting the Dynamite now detonate's it which has mixed consequences (yes it's cool to time the detonation to blow up the enemies but it's much less helpfull when you're already firing and dynamite's thrown into your line of fire next to you causing more unfair deaths)

SNES - This version has the fantastic Intro movie from the arcade

Mega Drive - Missing the aforementioned intro.

SNES - Skid is mapped to a button, it doesn't seem to make that much difference as it's pretty easy to skid with either controls.

Mega Drive - In the MD version you only have the choice of picking either Billy or Cormano as the other two characters are unavailable.

Mega Drive - You have to collect stars during the stages to access the bonus game.

Mega Drive - There's a new two-player Vs mode added to this version which is kinda' alright but very lacking in longevity as it gets boring pretty fast.

The Mega Drive version of Sunset Riders feels very much like a game that had a difficult development, one that probably took longer than expected and subsequently had to be rushed with compromises to meet deadlines, take for instance the fact that the two horseback riding levels are missing, but suddenly we have a new bonus stage with horseback riding that seems to be similar to the start of the original level two, maybe they started to create the second level ran out of time and converted the code into the new bonus stage? Or how about the fact that the boss of the train level has been swapped with one from a later (now missing) level, did they add him to the train level simply because his programming was already finished whilst the level to go with him was unable to be completed in time? The last thing I feel points to this being the truth is the general inconsistency of the graphics, level 2 looks as though it's actually going above and beyond the call of duty whilst some other levels look fairly amateurish, take a look at the second stampede in the first level, after the cattle have left look to the top half of the screen which is filled with detail and some parallax and compare it to the bare untextured bottom half of the screen which has barely even a rock to speak of.

So in closing the Mega Drive version has an unfinished feel to it and is inferior to the SNES version in most aspects, though it's actually still pretty good all things considered.