Something else to consider if you're looking into this for health reasons is that standing isn't necessarily any better. Studies have shown that it doesn't matter if you're sitting or standing because in both cases you're not moving. However, I believe standing, at least part time is still better because in reality you're not standing still, but rather moving around a bit, doing small side steps and stuff. When standing you're using more of your core and lower muscles too. Standing up also allows you to walk away and come back easier so you're more likely to not stay there for long periods without taking breaks as you would in a chair. Not that it's not easy to get up from a chair or anything, but it's probably more of a mental thing. Idk,that's what I've heard from several people and have experienced myself anyways.
Sometimes it's hard to keep a high degree of focus while walking.