That quote about cleaning being the first step of inspection is spot on... but I'd push back a tiny bit on calling it a 'spotless' plane. You don't need it spotless, just clean enough to see what's actually there. Overcleaning can actually hide things too if you're not careful with solvents and rags.

Have you checked if there's a Carpet America Recovery Effort drop-off site near you? In my experience, a lot of the big home improvement stores will take old carpet if it's dry and clean, but you gotta call first. Your mileage may vary on that one though, some locations just don't have the space. I've also had luck posting on Freecycle or a local buy nothing group, people will take cut-up pieces for mulch or garage floor covers. Take that with a grain of salt but it's worth a shot if you don't want to just dump it.

The older guys always seem to have one brand or type they swear is garbage and it's usually something they tried once ten years ago and never touched again. Dual-techs have been solid for me too, same Bosch line you mentioned, and I think a lot of the hate comes from people refusing to adjust sensitivity settings to match the space. It's like how my dad still insists that any car made after 2005 is "too computerized" and will leave you stranded. Stubbornness is a hell of a drug, same as it ever was.

Did you ever find a control transformer hiding behind a panel that nobody knew about?

My buddy spent an hour last Tuesday helping someone's kid figure out why their Roomba kept fighting a lamp.