Lots of potential is wasted.
The game is so ambitious starting with a first good impression. You start as a runaway driver struggling against the police. This police chase will remind you of Vin Diesel's own action films. After the mission is over you can start the open world exploration of the beautiful city of Barcelona. The environments are beautiful but not as detailed as the Liberty City in GTA IV (of course not!).
The types of the missions are the same as the Saint's Row series, with missions being broken into two parts: Main Missions and Side Quests.
As you know, the main missions progress the story, while the side missions provide you with rewards which make life easier for you in the open world. The rewards are the likes of increased car damage, increased Focus Meter (more on that later), new weapon caches, etc. The side missions are varied including taxi driving, police chases, car chases (in which you have to air jack a car by jumping from your car on its roof! And then bring it back to the garage!), car smashing (in which you have to smash cars using your car as a melee weapon!), the good old street races and so on so forth. They are fun.
One of the nice things is the focus meter. The focus meter is a circle at the bottom of the screen and it fills up as you perform certain actions (such as speeding, jumping, etc.). When the meter reaches a certain level you can perform some nice actions. You can boost your car's speed, you can turn your car 180 degrees and shoot the enemies chasing you in slow motion or you can do the same shooting while driving forward (in slow motion :D).
All of these were some of the good features.
Now about the bad ones. The game suffers from the lack of radio system which was seen in the GTA and Saint's Row games. You can't change the radio stations and the music is played randomly. Aside from the not so good soundtrack, there will be occasions when in the middle of a hot chase or action scene you will have to listen to a cool classic song which doesn't go with the situation.
Other problems are occasional bugs, arcade driving system, bad car crash system, drivers or pedestrians who don't care if you put a gun in their face, some bad animations, no graphic configuration setting (!), no keyboard button customization and the fact that the city is not full of life.
If the points in the last paragraph were fixed this game would've been a great addition to everyone's collection.