Unbelievably boring. Bought this as I wanted something with a bit of depth instead of the usual FPS, but this definitely did not turn out to be the case.
Controls are maddeningly unresponsive, you'll need an extra hand if you want to both keep your horse moving and see where you are going, and even then he'll get stuck on invisible ridges and walls every few metres. Camera angles are all over the place. Scenery is beautiful but completely devoid of life with no enemies or other characters to interact with. Colossus encounters are essentially a string of boss fights but are so mind numbingly tedious that you just end up wanting them to be over - which is unfortunate as they make up around 99% of the game. Disappointing as it could be an amazing game if the controls and camera were sorted and there was actually something interesting to do. Full disclosure - I didn't complete it but gave up halfway through due to complete boredom.