I( think they are a great idea, and priced very fairly, which I bet will soon move upward as they realize greater demand.

I like the fact they are basically all sprung weight but didn't see a numbers for total weight. I suspect the control/tank/compressor could be removed easily on a mounted say skid plate, and then reinstalled to help get the car up on the trailer ramps.
I like, I'd just have to remember one more thing when driving down the highway after turning off my turn signal. eek

Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.