Ask HN: Standing seats – all day use OK?

So about 5 years ago I cranked up the legs on my Ikea Galant to standing height and couldn't stand it for all day use, so went back to sitting position for the last 4 years, which isn't that bad with a Stealcase Leap as the chair.

Anyways, I've recently discovered these standing seats like the Focus Upright Mobis. How are these for all day use? I know I could get a height adjustable desk and vary the height through the day, but I'd rather use what I already have - which is a height adjustable desk, I just can't adjust it on demand.

And while on the topic, what are people finding is optimal for software development these days. My setup was built in 2008 - triple 24" 1920x1200 monitors. I'm do for a full redo of my office and am thinking that one large monitor may be best - with my laptop on some arm or something.

Thanks!