I convinced myself to buy my tractor after reading about a young kid that I knew who died feeding hay. His "vintage" tractor rolled. That was enough, I decided to get rid of my early 60's vintage D17 and step up to something modern. My ROPS sometimes gets in the way, but it has never been down. My seatbelt is not always on, but I am getting better, and so far the seat switches are all still working. I learned something a few months ago when I knocked the speed switch off the Xmisson cutting a bush, I used to tip the seat up when I was not using the tractor to keep the seat "dry." I was having some trouble with the seat switch at the time so I took the seat apart. What I found was that my keeping the seat up actually drew water to the switch. I cleaned everything up and was amazed at how simple that switch was. Now I leave the seat down all the time and I have never had a problem again. All I can say is that the ONE time you will need the seat switch you will REALLY need it. I have hit a deer on a harley, had two emergency landings while flying, and actually had an automatic opener save me while learning to skydive. Proper use of safety devices improves your chances of comfortable evenings. It is your choice.
PS, there are basically NO safety devices on my OLD plane. Recognition of what can go long is a practiced routine IF you intend to be an old pilot. ALWAYS recognize what you can do to minimize risk. My favorite phrase as a jumpmaster was that "..God thru you back..." When my "time" comes it will come, but safety devices are things that we use to reduce the "pain" from events when we are not "keepers.."
Check out this site and do what you will with what you know:
NIOSH Fatality Assessment and Control Evaluation(FACE)Program: Main page | CDC/NIOSH