Unless you guys already knew, stay away from the 3DS version as It suffers from the traditional Dimps experience/Very unpleasant...
The levels that were on the Pax demo were probably the better levels the game had to offer because after that, the game becomes a typical Dimps game with the slippery controls, stupid gyroscope gimmicks, and standard Dimps level design filled to the brim with springs and the often occasion speed booster. Super Sonic is obtainable but the effort to get him is tedious due to the annoying gyroscope controled special stages + He is not built for these stages as I found my self falling into the numerous bottomless pits due to the amount of speed I built up(without the run button being held. Like playing as Super Sonic in SA's Windy Valley and flying off the map at extreme speeds.
I will say though that there are still the occasional decent moments where I'm enjoying myself like the funny cutscenes(that are horribly compress) that are presented before almost every stage, the snowboarding section in Frozen Factory or successfully navigating through a level with parkour but alot of the time, I was almost tempted to wreck my 3DS.
Not sure about the Wii U version but it looks like it handles better.
And tbh, I would prefer they went back to the Unleashed formula for another game or so before they retired it.
Also Regarding the IGN review: I think there was a similar incident with IGN and the wonderful 101. The reviewer didn't understand the mechanics or how to play the game properly so he rated it average. : / Might be wrong here. Someone can confirm it if they want.
And back to Pokemon