Saw it last night at an early screening. It was a blast! Personally I'm more a fan of the first movie, as I think it toed the line between "kids movie" and "family movie" a bit better. There's some stuff in 2 that was more overtly for kids, but there was still plenty of fun for everyone. Idris Elba absolutely steals the show in every scene he has.
That said, Sega/Sonic diehards will probably like it way more than the first movie. The chemistry and interactions between each character are superb. Every character's personality is fully on display and accurate, brought to the big screen in fully glory. And there's a ton of easter eggs that will have me picking the film apart for days when I pick up the Blu-Ray. Definitely a worthy sequel!
Well, I'd love to stay and chat, but the gym closes in 1h22m and I'll already have to go through embarassing music instead of regular music in there - they put it in the last hour to demotivate people going in late