they require specific "clean" trunked trees to use.
That's my gripe with them. Has to be a somewhat skinny, tall, straight, clean tree that when I'm in it makes me look like a giant blob. Height is the only way to hide. I'm a big guy and stick out pretty far to each side of a tree small enough for a climber. I have a Summit and the max tree diameter is 22". I'm pushing 36" wide in the shoulders, more with hunting coat. By the time I'm 20+ft up a 22" tree it's actually more like 16"-18", and I stick out like a sore thumb.
I rarely have a problem with deer seeing me and spooking even in 12-foot ladders.
Same here except I don't have ladders. I don't have to be high in a lot of situations. A good backdrop so I'm not skylined is paramount, and even better if I have some undergrowth in front of me just below eye level. Seems there are few things to hide you above 12ft until you get high enough to be in the tree top branches. Between 10ft & 15ft is often the goldilocks zone.