I beat it on the default (easiest) difficulty using the Sega Mega Mouse. Given that this was originally an arcade game, I have no problem with its length.
I didn't feel like hooking up a CRT and digging out my light gun, so I decided to see if it was possible to beat it without the light gun. While you can have the cursor move at 2x, 4x, and 8x speed with the standard Genesis controller, I don't think it's possible to beat it with a controller unless you repeatedly guess correctly as to which enemy will appear in the randomized sections. Even with the mouse, it was still pretty difficult on the lowest difficulty setting, Deputy. I tried the higher difficulties, but the amount of time you're given in the randomized sections to shoot the enemies seems to require guessing which enemy will pop up, setting the cursor on that spot, and hoping you got lucky and chose correctly.
The game consists of four areas you have to clear of McCree's men to free the sheriff from the jail, then save the mayor at McCree's hideout, before finally killing McCree in a shootout. Each area has a lead up section where you have to kill 1-3 men and then the main part. The lead up sections are all scripted, while 2 of the 4 main parts have randomized enemies. Even on the easiest difficulties, for the randomized areas, you have maybe one second to target and shoot most of the enemies. On the hardest difficulty, you have what seems like less than human reaction time to do so for most of them. The grainy video also doesn't help, although the game does give you a flashing spot on the enemy's gun barrel to help with the more difficult-to-see ones. There is one enemy that you cannot see and just have to know he's there, but luckily this is in a scripted section -- you'll still die from him the first time, which is a load of bull. When you get shot, or shoot a friendly person, the undertaker has a few lines that made me chuckle. It is nice that you don't have to replay the lead up sections on a continue.
If you do give this game a try, be aware that a standard controller has to be in port 1, while the light gun or mouse has to be in port 2. I don't know if it was because my mouse has a really tight fit in the controller port, but the game wouldn't recognize it most of time, and when it did, if I returned to the main menu, it thought it was a light gun, requiring powering off and on the console and hoping it would recognize it.
