If you don't have some type of OI (orthostatic intolerance, where standing in and of itself causes problems) then it's hard to say how helpful a perching stool would be. But perhaps anyone with an illness that causes low energy and fatigue might be helped by sitting down?
But if you do have OI then I think it could be helpful. I have a chair in every room in the house, and a seat in the shower, due to my problems with OI (specifically, Neurally Mediated Hypotension). Even though I am able to stand for a minute or two before my symptoms start, and it took a full 20-30 minutes of standing still before I passed out on the tilt table test, I have found that sitting down when doing any task at all helps me quite a bit. This sitting down is
in addition to breaking tasks down into small units (few minutes of tasks, few minutes of rest). So, for me, it's not an either/or situation.
... it's not generally my legs that are the problem, it's core and lower back fatigue/pain that limits me ...
Like you, when I get symptoms from standing it's not my legs that are the problem. But my symptoms are dizziness, nausea, muscle twitching, increased heart rate, feeling foggy headed, sometimes a clammy cold sweat, and an urgent feeling that "I have to sit down right now." It was years before I recognized these are all symptoms of pre-syncope (the period right before fainting) because I never actually faint, I only get the pre-syncopal symptoms.
Does anyone else have such a device and if so does it help, how do you deal with moving it etc (in short is it more agrivation than its worth or is it useful)
I put "sliders" (here's one brand -
http://www.magicsliders.com/ ) on the feet of my kitchen bar stool and the chair in my bathroom (I sit down to brush teeth, fix hair, etc.). They make it easy to slide the chairs from place to place. If I had to lift that heavy bar stool then, yes, it would be more trouble than it was worth! Sliding it across the vinyl floor works well.
Another thing to consider is where to put your feet. My kitchen counter is obviously too high for my feet to reach the ground while sitting on a bar stool. Dangling feet is bad for OI so anyone with OI needs a seat that has a place to brace your feet. I've also found that a back rest is helpful (to lean back rest for a bit in between doing some small tasks).
It suddenly occurs to me that I'm not sure what a perching stool looks like. Maybe "perching" means you're just resting on the edge of a seat and not really fully sitting down? Hmmm, now I wonder whether any of my input has been helpful since I have no idea what this thing is!
Okay, I just did a google search and found an example -
http://www.elderdepot.com/customer/product.php?productid=1994
For me, at least, a regular bar stool, with a place to put my feet, would be a lot more helpful/restful than what is in the photo. Not only can I slide my bar stool around (it looks like you do have to lift this perching stool to move it) a regular bar stool looks much nicer. And the perching stool doesn't look high enough to do any actual work on the counter. I'd have to lift my arms up to get them high enough and trying to do work while lifting my arms up higher is not a good thing.