well...practically since I WAS a boy.
I've run them on most everything, from my old Bultaco MX bike, to a VW Thing, & currently, the VX.
Yeh, I occasionally throw a cel...but I treat that as a "time to douche the MAF" reminder light...
It's usually right after cleaning/re-oiling the filter, as I've always been of the "more is better" mindset...(just check my "all U can eat waistline")
For me, it's worth the extra effort to gain a few ponies.