First off, I believe that Motorstorm is a truly great racing game, and it's a great exclusive for a console to have, one that the PS3 particularly needs. The game is revolutionary in a lot of ways. While it's not the first racer based around dirt tracks, off-road etc, it is the first truly great racing game based on dirt. When you take into consideration that this game was a launch title, it's even easier to appreciate the phenomenal effort put into making this game what it is.
It is, however, not without flaws.
Map Variety
Unfortunately Motorstorm has very few maps to race on. Considering the number of tickets and race challenges within those tickets, the number of tracks available simply is not sufficient. If you have to race 60+ times to finish the game, 7 tracks just don't provide enough variety. These tracks are also the only tracks available for online racing, unless you choose to pay to get more. It would be nice of Evolution Studios to give us a few more free tracks.
Split-Screen
The problem with Motorstorm isn't the implementation of Split-Screen; it's the non-implementation of it. Motorstorm, quite simply, does not have Split-Screen for racing against your friends. It's one of the simplest features to add to a game, and one of the most important. Luckily they've decided to add it for Motorstorm Pacific Rift.
Car Roster
There isn't a big enough variety of available vehicles in Motorstorm. While there are 7 different overall vehicle varieties, the variety of vehicles within those broad classifications is pathetic. The only difference between these vehicles is the look/colour scheme. None of them have different stats, so there are effectively only 7 available vehicles in the game.
Regardless of these problems, Motorstorm is a great game. It is definitely worth the purchase, especially with the current low price of it pre-owned. This game deserves a rating of 8.9 in my opinion, a must-own for all PS3 console owners. If you don't own this game yet, you should go out and pick it up now.