I bought this to replace my previous Pearl throne as I have been using it to work from home for the last year (I did used to be a drummer, honest!), so the cushioning and support had finally given out, requiring [a long-over due] modern-replacement.
The D-3500 was easy to set up - rotational mode for me - and the memory foam is excellant, offering fantastic, comfortable, even
support (especially as I am sitting on it for several hours a day).
The stand is very stable and strong, with a good range of height adjustability.
The only quibble is that in rotation mode there is no way of having the cushion attach to the stand at the same time (which my old throne did), so if you pick it up by the cushion to move it, it will just lift off the stand: not so much an issue for me as I am behind a desk but for those using it for it's actual drumming/gigging purposes, it might be a faff when you have to remove the cushion and replace it every time you move the throne around.
I might not be using it 'properly' behind a kit, but after years of drumming with a previous version, I see how much of a benefit the D-3500 would be to drummers: solid, stable, comfortable, easy-to-use, with the adaptability of attaching the backrest (D-3500BR) should you wish to.
This is a great investment and addition to any drummers' equipment.