The main reason is the cache (which makes a huge performance difference) is turned off at the moment - we are working on stability first then performance.
/MikeJ
I wouldn't worry too much, the speed of the minimig looks wrong. A real 68000 nearly as fast as a 25mhz 68030? Unlikely. Sysinfo thinks it's clocked at 52mhz. Thats a serious overclock for a 68000 :-)
It's more likely that there are emulation bugs that cause the timing to be wrong. If they are all based off minimig source, then they might all have the same problem.
The results are meaningless, I think you'd notice if you were half the speed of a real 68000.