Having replayed it recently, on the 360. Well, I don't really mind it, and you can get through the story without driving too much. The sidequest planets don't have much variety about them, and the Mako's controls are erratic at times, and if you truly work at being a completionist at least 20 percent of your total gameplay will be driving across the mountainous planets.
It's not too bad but it can get a bit dull if you don't spread out doing the sidequests across the story.