An excellent action adventure game on the go.
The frame-rate is decent, but at times, such as being in a huge gun fight or explosion, the game tends to lag. But only for a second or less. That is nothing to hold back the actual gameplay whatsoever. Surprisingly, the load times are fairly good in this game. The PSP is notorious for its tremendously flabbergasting load times, but this game fights that title.
There is a medium amount of actual main story missions, and a hefty amount of pastimes(Mini-games or side-missions) and hidden 'goodies', if you will, to keep you interested in the game for a good while after you beat the main story. All pastimes, hidden packages, as well as the main missions go toward 100% completion of the game.
Even though Liberty City Stories is on the little bitty PSP 480x272 screen, the game still has below average or average PS2 graphics. That is great for this system, and the good sound makes it even better. A variety of radio stations are also included when you are in/on a vehicle.
The quality and replay value of this game is very high. If you like, own, or can't get enough of other GTA games, you MUST buy this game. It is not one to pass up.
(I'm not good at writing reviews...)