I have the bosch bigfoot. Runs great, wouldn't exactly call it lightweight though. not sure how the bigfoot base wieghs in compared to a 7 1/4 base... Also I have never owned a skill sidewinder, so can't say whether the bosch is better or not. It does run great though.
The dewalt saw I was referring to is the one with the fiberglass base. I would buy that saw if my makita dies today. And... that blade that kerfed the rock, it still cuts good. I was ripping some 2" pine yesterday with no trouble ( -;