Yeah. After 54.8, there aren't hard levels until HM.8. HM.6 is a bit hard, but you shouldn't lose more than one life there.
In TT, the few hard levels are 8 (death almost unavoidable), 9, 11, 13, and 15. There is a bonus dimension in TT.10, but the levels are some of the hardest in the game, and the prize is just 90.000 points.
