jekjr,
It's not so much lack of concern over lawn tractors, but due to the nature of the industry. You don't see a majority of "lawn tractor" manufacturers(Husqvarna, Cub Cadet, etc.) that sell those machines as explitly being a "Commercial" mower even though it is a given that many Lawn Care maintanance companies use them. Now the big ole John Deere's have them, but mostly because that model line evolved from "John Deere tractors"...not consumer "lawn tractors". Good point, though, in regard to singleing out ZTR's. And like user Ric has pointed out, what about standers, walk-behinds with sulky, etc?? Can't really put a ROPS on those, right? Even though my Avatar shows my ROPS down, I have since added a sunshade so now it is always up. I understand when time is money, your point about an operator's focus being downward, but scanning the area before beginning and remembering where overhead obstacles may be encountered(or maybe a pre-walkthrough placing small red flags in the ground to warn of overhead obstacles). I have a relatively flat lawn with mild grade but have not been wearing my seat belt. I hear ya about bailing out versus being fastened to the machine but if the ROPS is up and the seat belt on if I roll it won't I be OK(just hanging upside down)???? If not...the ROPS/seatbelt is useless as the tits on a boar hog:0) I am leaning towards ALWAYS wearing my seat belt when mowing going forward unless I can be convinced I'm safer without it(and the likelihood of me turning over is relative to me watching out for my mimosa trees:0)