I can only agree with createcoms as I bought the game and was a little bit disapointed about the speed (not exactly smooth and fast on my A1200PPC 240Mhz/68060 permedia2 640x480) and the lack of network support.
On the other hand, JD also wants to make money so even if people are bored with GTA style game, I would assume windows version would sell at least as much as amiga version.
Never played any GTA and besides the 2 points mentioned before, I like payback very much (specially the music).
LionStorm
