I sped through them for enjoyment, I like to play without worrying about extras on the first sitting and then go back if the game peaks my interest. I wasn't even aware that you could customize Sonic with power ups until after defeating the final boss. If you're interested in challenges and the likes (some of them are enjoyable, and include new sections in old levels) there are about an extra 3-5 hours worth of them, I just finished 100% on Green Hill Zone. The music is amazing, the classic levels made me feel like I was playing what Sonic 4/Rivals should've been. Seeing some of the stuff from the Genesis days with the 3D models of today (Death Egg Robo from Sonic 2 had me pumped the entire time) gave me a deep feeling of nostalgia (simply because of all the horrible games released until this point). I hope that Sonic games in the future follow this formula, hell they should just consider making a sequel to Generations with more levels re-done from the 90's era, followed by fixing up the 1-2 decent levels from 06 that remain and some of the speed levels from unleashed touched up as well. Also