By the way - I have a fully working copy of SFIV now - including online play - I'll write about it later in the proper thread. :-P
So you won't buy it anymore? :P
I will, because I like to pay developers that released a cool game and I already know that I will be playing SFIV a lot.
However, here's a little tip - apparently Games for Windows Live is quite retarded and you can use ANY Live key that comes with ANY game to play ALL Live enabled games online. 0_o
So - if you don't want to pay so much for SFIV because you're not certain if it's up your alley, then you can buy any old game for like 5-10 Euros and use the key to register the... uhm... "unofficial" version of SFIV. ;-)
The earliest Live enabled game would be Halo 2 for which I sadly only own the review version but I found that Kane & Lynch is sold quite cheaply because it's such a shitty game. :-D