If you've played Race for the Galaxy, then you'll immediately have an inside view to this game. So far, in my experience, this game is much easier to help new players understand and get to do well in than Race for the Galaxy. There are less details to remember. I also like the random aspect of the roll phases and the specialization of the individual dice. It makes the game more interesting.
I've tried to consider if I would keep Race or Roll over the other, and I honestly don't know. While the games have similar themes and play roughly the same, they have quite different feels. First, planets actually feel different from developments. Race only made a distinction when resources were produced, but otherwise planets weren't any different from developments. In Roll, planets give you dice, and developments give you abilities. Also, the distribution of planets and developments is equal because every tile is double-sided with one planet and one development. Sometimes you just hope to get lucky in Race.
The price of this game feels a bit high, but most of the game is thick, durable cardboard (and you don't need to sleeve your cards). The plethora of dice also add to the price (dice are surprisingly expensive). But despite the major cost difference, I like pulling this one out more than Race most of the time. If you like Race for the Galaxy, then buy this game, too!