Worth giving a go if you're an action fan, a better game than many give it credit for..
SF2 isn't great graphically and the full shadows are horrible and should probably have been left out of the game, although its simple enough to keep these turned off. Some of the environments are better than others, the jungle area is quite memorable but some areas like the first one at the hotel are very poorly put together. A bit of a mixed bag really, like some of the levels were designed by the pro and some by the intern.
SF2 tries to break out of the original formula of SF and that's a mistake, they have an abortive stealth element and one of the early levels uses it extensively, they've also added automated squad style action in places but that does work better. Nothing really detracts from the game too much and on the whole its still good action fun.
There is a plot that's slightly more memorable than the original and is filled in buy sequences in the game's own engine, some of these actually work quite well and look nice. The weaponry is good, improved from the original but just as meaty (in more ways than one), yes the weapons are a pleasure to use and there is even the ability to dual wield the pistols and machine pistols in the game. Additionally a lot of the weapons can be upgraded with standard addons like scope/silencer/red dot/torch etc..
All in all a better game that it first appears, definitely worth sticking with and playing all though, could have done with a little more dev time to polish it up but there your go.