I was really pleased by how Modern Sonic handled in the new demo. The controls are really tight and responsive, particularly at low speeds. I tried just messing around in a few of the more open areas, walking around and trying to make precision jumps. It's like night and day compared to the out-of-control train controls of Sonic Unleashed. And it's also a big step up from the version of Generations I played at San Diego Comic-Con. (It's nice to know someone over there was actually working to improve this thing. Go figure!) I can't believe it took them this long to get it right... especially since it was something they basically ALREADY got right in the original Sonic Adventure... but they've done it. Sonic controls properly in a 3D space. Amazing!
The modern Green Hill zone is shallow, but fun. There are a few branching paths here and there -- primarily in the 2D sections -- but as we all know, it's a very simple and linear stage compared to the later modern stages. I'm really curious to see if the more complex and open levels still manage to feel as tight and polished as this one does, or if they devolve into unintelligible chaos.
There are tweaks to classic Sonic's handling, too. On the whole, they make him feel closer to the original. But a surprising side-effect seems to be that he no longer has enough momentum on feet alone to carry him through a full loop. Running towards a loop at full speed, without spin dashing or hitting a boost pad, will get Sonic ALMOST to the top of the loop, but not quite. The loops aren't scripted or anything -- hitting them at different speeds still takes Sonic up and then back down again accordingly and naturally. But a regular running pace just isn't fast enough to get him over. His top speed is too low. You need the extra kick of a spindash. The physics feel good to me, and I'm happy with anything that behaves consistently and predictably... but still... it's just kind of weird.
That's my only real niggle with what I played. They've made a ton of smart, little changes. Everything looks and feels great. The framerate is higher. The background for 2D Sonic has been tweaked a little to contrast more strongly with the foreground. They removed the trip steps. They adjusted the "slide under the barrier" obstacles so that the prompt now comes up early enough for you to react comfortably. They made changes that, I swear to god, must have been based on actual playtesting. The thing is astonishingly polished for a Sonic Team game. We'll just have to wait and see if the actual levels they've built inside this pretty, technically solid box are... you know... any fun to play.