Nice pack, although I feel like it was a bit too easy for a "time trial" pack. I am of course okay with easy time trial levels, but I felt like the timer didn't add anything to the experience.
Also sort of dislike the amount of walls in place; BBT has compact space for level creation, you gotta make the most of it.
I found the finale background levels to be the best, since they fully endorse the fact that the pack is kinda easy and removes the checkpoints.
That's just my take though, for this REALLY old playlist.