I use the harness on my plastic Bubblers. I forgot to put it on before knocking out from the kettle once. I only forgot once!
I dropped a glass carboy once. On my foot. No, neither the carboy or my foot was broken because it rested on my steeltoe shoe, and it was from a low height because I was going down 'losing it', but it was close enough to catastrophe that I ditched the glass for the next batch. (I opted for buckets next) I don't think I'd ever go back to glass unless they were 3gal and then likely only for Mead as a secondary, if that.
Depending on your setup, you could combine the harness with a pulley system. I saw pics years ago where a brewer rigged up a pulley on a swing arm so he could hoist his carboys up, swing them over his chest freezer/chamber, lower them down and of course the reverse, even setting them on the top of the lid after closing for transfers. I currently use a stand-up chamber, but if I had to switch to a chest model, I'd highly consider such a contraption!