I used a clamp and an arm to mount an 18" + 8" stack alongside my ride onto the stand.
It works if I don't set it up in a dumb way, but it doesn't feel incredibly stable. If you plan on doing this, I recommend that you try it in-store with your own cymbals first and switch them around a bit to see if there's a way the set-up could work well.
Personally, I would just use one cymbal on these stands for live gigs.
Other than that: If you don't put too much weight on them, they do exactly what they're supposed to and are pretty well made.