SR3 technically didn't get "dumped", Sega themselves published the full game as an "update" for arcade owners to download. They didn't bother with access control though, so others quickly grabbed and then hacked it...
Yeah, SR3 is extremely easy to set up on a PC, I wish I could say the same for SR3 on PS3/X360, I have a hard time finding those since I never got around to downloading them when they were for sale.
As far as I know, there was never a Sega Rally 3 as such on the PS3/360. There was Sega Rally Online Arcade, which was similar but not exactly the same. Online Arcade actually had some extra tracks I think (not sure about that), and it had motion blur, unlike SR3. On the other hand, SR3 ran at 60fps whereas I think all of the PS3 and 360 versions ran at 30fps. SR3 also runs at 1080p, and I think the console versions ran at 720p.
SROA is the official SR3 console port.As far as I know, there was never a Sega Rally 3 as such on the PS3/360. There was Sega Rally Online Arcade, which was similar but not exactly the same. Online Arcade actually had some extra tracks I think (not sure about that), and it had motion blur, unlike SR3. On the other hand, SR3 ran at 60fps whereas I think all of the PS3 and 360 versions ran at 30fps. SR3 also runs at 1080p, and I think the console versions ran at 720p.