For 3M, if I remember correctly, the time limit I selected was exactly 15 seconds more than the part of the level that took the longest to solve when played separately. Because I'm not the most economical with time, you probably have about 20 extra seconds. Which, given that you have to balance 3 rather tedious (again, I apologise for that) parts of the solution with only 20 seconds to mess with, is very, very tight.
When I make the rest of the levels and re-order my sets, 3M will be 4.28. The last level will remain last, and 4.29 is a conceptual level that I haven't gotten to designing yet that WILL, I'm fairly certain, be the hardest to figure out level I've ever made.
Daigoro would be absolutely fine to review next. I think I've gotten most of them except a couple of the trickier ones, and I'm sure with a bit more patience I can get those that I'm missing, which means I can be a reviewer for that pack. Again, I think my pack took so long because I can't review my own levels.