I have a "Cool Living Stand Up Desk" at home that I bought on Woot a couple of years ago. Note that it's a hand cranked height adjustment. Currently going for $220 on Amazon, but the slow adjustment process is an annoying barrier to switching positions and keeps me from doing it as often as I'd like to.

https://www.amazon.com/Cool-Living-Stand-Up-Desk-Black/dp/B0...

I'm otherwise pretty happy with it, but it's my home desk not my work one. If you're looking for a desk to use for full time work I'd recommend an electric or something with a counterweight or spring system to allow easier changes between sitting and standing.