I received my original Ab Roller when I was 16 or 17 and was excited to see the new re-vamped version and purchased it for my stepson. One key feature that they removed, and is proving necessary for me as I try to use it on my hardwood floors, is the base that held it in place but allowed it to roll.
It might work better on carpet or a more non-slip surface like at the gym, but not so much on hardwoods.
Other than that, I don't really see anything else to really complain about. I love the added features but wish they had left the bases on.
Review about: Ab Roller Evolution.