Sonic Colours
Polished that one off this afternoon (the Wii version is what we're talking about here), excepting a handful of the Simulator levels. Anyway, if I'd played this in 2010, I reckon it would've taken the 'Biggest Surprise' award, because it's really quite good. Not without some demerits, but definitely worth playing. I don't blame you for being apprehensive. Seriously though, it's a fun Sonic game.
The main area where it excels above its predecessors is that Sonic Colours has a much smoother feel to its control scheme, and moreover, the levels are, for the most part, designed around the controls. I had the misfortune of being gifted Sonic Heroes back in the Gamecube days, and with that game, not only did Sonic move wildly, but the levels were made with cheap death traps that were far too easy to go zooming into because of how uncontrollable the characters were. In Colours, the controls and the levels are way more synonymous with each other. I was able to anticipate what was ahead of me much better, plus Sonic can now drift around corners. The powerslide is unfortunately not always reliable - I'd say about 80% of the time, it's fine, but occasionally, it over-steers and cuts your momentum, and I didn't know how I had done it differently when that happened.
As with all 3D Sonic games, there's a fair amount of running straight ahead into the screen, where your input is fairly limited, although it seems there's less of it than some of the others. Sensibly enough, the 3D platforming is usually pretty simple, while the twitchy stuff is reserved for the 2D sections. The good thing about Colours is that, during parts of levels when the movement is somewhat on-rails, it makes a spectacle. The graphics are bright, vibrant and flashy, which does a lot to sustain those sections.
The big additions for this game, of course, are the Wisp power-ups. There's 8 different species in total, and the ones that are most enjoyable are those that let you explore for little nooks, with the Rocket and the Drill having the broadest applications in the levels they feature in. Essentially, this allows you to play a level multiple times and take completely separate routes to the end. For example, I might go through a stage and think "Hm, I wonder if I could have used the Rocket at that point", then I'd try it and find a new path with a Red Ring (needed to unlock secret levels). I really like that aspect of it. Some of the other Wisps, like the Block, are less interesting because it's blatantly obvious as to where they must be used.
There's a couple of sticking points that detracted from my enjoyment. At the top of the list is the perfunctory story elements, specifically the voice acting. I kept reading that they had brought in an entirely new voice cast that's supposed to be much better, but that's not the impression I got. I still found the characters to be just as grating and cringe-inducing as before. Further down the list is the pointless quick-time events that come into play every time Sonic launches off a ramp. You just hammer the A Button for a few seconds; it adds nothing to the game.
Regardless, I believe Sonic Colours is worth picking up. It is a very surprising instalment in that franchise.