Been playing Race The Sun, it's an entertaining game, the gameplay is pretty simple, just avoid obstacles and pick up certain objects.
The levels seem to offer some variety, but since you always start in Region 1 after you die, it takes awhile to get to the more interesting parts of the game.
In terms of level variety, the game has different "worlds" per day (a world being the set of levels that you play in that particular day), but since I bought the game today I can't really comment on how much variety that will introduce into the game.
The game also features a leveling up system where you level up by doing certain challenges the game sets you up to (such as moving X miles, doing two perfect regions).
By leveling up you'll gain extra abilities.
Oddly enough they decided to lock several base game features off level 1, which you'll be missing a few base game features the first time you play, it's not a big deal since you'll gain access to them in a few minutes, and it serves to pace the player learning. So I can understand what their aim was with that decision, ultimately it still is an odd choice since it makes the first interaction with the game be less interesting than the game really is, and first interactions with games (especially Indie games) are important to capture people attention.
All in all, from the near hour that I've played the game, I would say it's rather enjoyable game and that I can see myself playing it a lot to kill time or just challenge myself, $10 might be a bit too much for it, I feel $5 would probably be a more adequate price for the experience.
Damn, I thought a kidney is worth more than that.
From what I hear, GPU's around that areas of the world are just that expensive.