This was so fricking fun!!! I am amazed at the level of polish the game had, and the great feedback from jumping and landing and going faster and all!! The first time I did the sliding thing felt soooo very satisfying as well, you got the camera movements so well! I made it all the way through and the final cutscene caught me very off-guard as well hahahahah :b
As for the difficulty, I personally really liked it. I died a couple of times on every stage, and even though it technically can be seen as unfair, I really love games like Sonic Unleashed, where you have to memorize a stage to get high scores and such! Definitely up my alley - I loved it!