don't see why not. Friend of mine is doing their slim line model next weekend. I think they realise patches for games so it works online or something i'm not really sure. (ok so the friend is me !)
Since it voids your warranty, the guy who's doing it for me, you pay $50 extra and he gives you a 1 year warranty, not just for the mod chip and installation but if your ps2 burns out or stuffs up or something in a year he'll replace it.
Only gives it on slim models because there is something about their lasers burning out (happens on both modded and unmodded consoles).