From: Jeffrey Schwartz

>> Back when I was into moto-cross the rule of thumb, for motorcycles anyway, was that one lb of unsprung weight = 3-5 lbs of sprung weight as far as handling was concerned...
>>
>
> I wonder how that changes with "active suspension" technologies?

Well, the active suspension will need to be bigger and more powerful if it's controlling bigger wheels, so there's a fair chance that it's even worse with active suspension. However, just cutting down the number and length of mechanical links can help, and there are control advantages to being able to apply force to each wheel separately, so one motor per wheel has likely benefits no matter what.