I've got mine air cup suspension from
Stanceparts | Air cup lift system
I must say that I really am 100% satisfied, the quality is really good.
So I don't agree with your opinion, However, I use air cups of stanceparts.. so it's a bit different. I'm using it for 3 years now, never had problems... and still use it with every ride!
You can find all the info on
Air cup suspension | Stanceparts