Playing with only 3 DSs (and looking to close 4 in some circumstances) means larger gaps at the start of the cycle and less bonus repeats at the end:
Level 0 to Level 1: 10
Level 1 to Level 2: 10
Level 2 to Level 3: 10
Level 3 to Level 4: 9
Level 4 to ...
Level 0 to Level 1: 10
Level 1 to Level 2: 10
Level 2 to Level 3: 10
Level 3 to Level 4: 9
Level 4 to ...