I bought the full version of this game.
The game in itself was great. I enjoyed every minute of it. The big thing that troubles me is that I paid $15 for a game that took me exactly 2 hours and 45 minutes to beat. And by beat I mean found and retrieved all 20 of those little trinkets and got the second ending and mini game. I am just as disappointed as I was when I played Portal. The full game is just to short and has no replay value for its cost.
Bottomline: it is a well-made, enjoyable game but is just not worth its $15 dollar price sticker. I recommend for others to play-through the game, but no blow $15 dollars on it as I did. Wait around, there will enviablely be a free version floating around somewhere.