Stand?? Hmmm, never thought of that. How stable are they? I feel like there would be a bit of play once the main bar is quite high. Also, how is the grip on the castors? Are they usually made of rubber? The reviews on these higher end stands are really good.
The bases is cast iron; there are cranks that bring the wheels up into the base so the stand sits on the floor. Mine is a Calumet and has no rubber or anything and man, it doesn't budge. The wheels seem to be hard rubber, and they have lasted for about 15 years and it still rolls fine.
When the bar is all the way up, with a 4x5 cambo and and the big Majestic crank-head, it's very stable, certainly enough for a cable release. Every few years I tip it over and tighten the column bolt and it's pretty rock-solid. For very high overhead work with big cameras, you want to be pretty still, don't bang the camera around, etc. But I'd say it's more stable at 7' up than any tripod I've experienced - especially for shooting straight down or at a steep angle where a tripod is frightening.
I use it to this day with my DSLR for product shooting or with a video camera to shoot effect plates and things like that. It just beats the hell out of any possible tripod as far as tweaking up your framing. if you have a studio space, it's one of the best things you can own.
You can detach the center column for moving day, too. One of the most fab things I've ever bought.
I also own an 8' kessler camera crane, those are about $1k plus a sturdy tripod and head - like, very sturdy! It's really wicked for overhead shots (since it hangs well over the work vs. a center column and arm) and I have used it for stills. But to really sing, it needs a head on the business end too. For most shooting, it doesn't have the convenience of the stand for adjusting height, needs a lot of counterweights (say, 18 - 22lbs) for big cameras, etc. but it breaks down into a portable package. Sometimes I just use it as my "very very tall" tripod and bring a stepladder. Camera ends up at about 7' in the air.