however, i'm not sure why you'd want to do that in the same house...
the ONLY benefit i can see, is to allow both players their own dual shock control (you can only use digital control for 2nd player normally)
you see, the game will be slowed down because of all the synchronizing, PLUS the slower machine will drag down the faster one.
it might be more fun to simply play 2 players with the faster machine. you can also do that pushing trick that way