I use the KM90, I like it but it is heavy. I also do not like the Sthil autocut heads. You have to ram them hard to get any string out usually. And they are not the easiest to load with string. But all in all, more positives than negatives for the Stihl.
7x14 Stealth SE Enclosed with 48" side ramp
08 Toro Z400 48" deck, 21HP Kaw with EZ Vac twin bag
09 Exmark Turf Tracer HP 36"
21" Toro SR4 Super Recycler
Stihl KM90 Kombi w/ straight shaft trimmer & tiller heads
Husqvarna 125B Blower
Turfco XT5 Aerator
Turfco LS-22 Overseeder
EcoLawn 200 Applicator
I can do all things through Him who gives me strength.