This game is ported from the PSP version which is why it has a cheap price-tag. The missions are designed for the PSP so they aren't as long as GTA missions from previous titles. Even though, at a price like this, it's well worth buying.
In this game you play as Toni Cipriani three years before the events in III. For most people, this isn't their first time in Liberty City because of GTA III and therefore there won't be lots of discovering and exploring. The graphics aren't a huge improvment because this is a PSP port which is dissapointing because they could've been improved on.
Boats, bikes, cars, ferrys & trains are the only means of transport here. Absent are helicopters, planes & bicycles. The customization of Toni isn't as vast and detailed as San Andreas; instead you unlock outfits as you go along.
This isn't a groundbreaking GTA title but it's still a good game.