The rain let up long enough today for me to get two accounts done, so I finally got a chance to use my new Stihl FS 90 R trimmer. These are weekly accounts, St. Augustine grass mowed at 4 inches. It was very light, the same weight or less than my old Echo SRM-210. Started up easily, 2-3 pulls cold, 1 pull warm. I loved it. It has great power, just rips right through the weekly growth like it's nothing. The guard on this was better at shielding the grass than the Echo, my legs weren't covered in clippings like they usually are. At one account, there was a small area of overgrown weedy brush like plants that I neglected to cut down before, so I used the trimmer on those. It cut through them with no problem where with the Echo I would have to start at the top and work my way down. Not much vibration. Someone posted here about how some 2 cycle trimmers "grab" the turf and take a bite out of it when on full throttle, this one does not. The bump head works like any other bump head, nothing special. Overall, I think the FS 90 is a great trimmer. I don't understand why everyone hates the 4mix engines.