There are many street fighter games, and fighting games for that matter. This is pushing for best of the lot.
Yes it's street fighter at heart, but it has great characters, great 2D graphics, fast, frenetic gameplay that is fun for the beginner and rewarding for the seasoned pro, and has lots of replay value due to the fact you can unlock every character that has been in any of the "Vs" games.
The biggest testament I can give to this game is that 6 years after it's release, and 2 years into the next gen consoles, it still cost me £35 to secure a used copy, and I was lucky. Some copies are going for around the £70 mark. That should tell you how good this game is.
I am so annoyed with myself that I traded this game the first time, and then had to pay that money to get it again. If you are lucky enough to find it (it is rare now), buy it. If you are lucky enough to find it cheap, buy it or I will personally **** slap you.
Definitely one of the best street fighter and fighting games all round. Time doesn't diminish it's joy.