Interesting puzzler, but gives little satisfaction and is based on the novelty of its strange geometry.
The graphics are interesting, but not really much to look at, and I think the main problem from this game is that there is absolutely no satisfaction from solving a puzzle. In other 'First Person Puzzler' games you are rewarded with plot advancements, witty dialog, and that feeling of progression. You don't get that here. There is not plot, it does give some interesting philosophical sentences after a puzzle sometimes, but other times it doesn't give anything interesting. And, the worst part, you always end up in the same place.
Every time you finish a puzzle, it takes you back to the same few rooms. This quickly gets tiring and frustrating, and removes every bit of satisfaction from solving puzzles from this game.
And for £15, you don't get alot for your money when you look at other similar games in its price range, such as Quantum Conundrum. And even after getting this game in a 25% off sale, I still feel like I've been tricked out of my money, like this game tricks you into going in circles.
In short: If its on sale, its worth looking at. The mind-screw effects are interesting, but if like me you've come prepared for the mind screws you should consider spending your money on something else, as without the mindscrew this game has very little left for it.
Edit: Most games give the effect of 'Omg, its been 20 hours, it only feels like 2!' Well its the other way round in this game. I felt like I've been at this game for ages, but it's only been 2 hours. After looking at other reviews by me of other games in this price range, I've lowered my score from 6 to 4.5, as it just doesn't entertain you for long enough.