Bad. First of all, there is nothing new from the PSP version. Graphics- crap. Those graphics were hot on the PSP because the PSP isnt as powerful as the PS2, but when the graphics are on PS2, its shit. Sound - crap. Not the sound effects, those are fine, but the soundtrack, holy shit. Firstly, there are like 4 or 5 songs on each station, while the regular GTA had like 7-10 songs. Gameplay wise, its just like GTA, but it is missing some of the stuff from SA, also, a lot of the better things are gone. For example, you cant climb up walls, you cant swim, you cant crouch, you cant do any of the GTA upgrades.
If you dont want to read all of that, all I wanted to say was R* should have not been so lazy and added more elements to the PS2 version as its on PS2, LCS is crap compared to modern PS2 games.