They are actually what the game looks like. It all ends up looking the same as 256 colors at 640x480. The graphics are just plain embarrassing. Fortunately, if you can get past the poor graphics, the games can be quite fun. The sounds are basically what you can expect from a port of this sort.
Music is very synthetic, but the voices and sound effects are on par with other systems.
I will venture to say that the music of the old Super Street Fighter 2 Turbo version for the PC is better than either SFA or SFA2. Just make sure your rig is set up so that both people are using controllers capable of multi-button games, or else it just wouldn't be fair. In the end, it's really all about whether you like this sort of game or not. I don't think Capcom made much of an honest effort in making these games look good on PCs, probably because they don't think there's much of a market for fighting games. I'll venture to say the reverse, that there isn't much of a market for fighting games on PCs because the translations are almost always so poor.