If your setup is 060 optimized, use 68040 setting in WinUAE. There is very few 060 software that does not run on a 040 (I don't know any).
General rule for emulation is, the more complex the emulated processor, the slower is the emulation. Following this rule, 020 is better setting than 040. But there is no noticable speed difference between 020 and 040 when JIT is enabled.
Bye,
Thomas