I have it on my 830 used as a daily driver. It was pretty buggy to start, but after a couple of hard resets and some fiddling, I've got it to a point where it's pretty usable. Some issues:
-Downloading from the store beta is a hit-or-miss affair. I just kept trying and eventually I got everything I needed. You may have to go back and forth between the old store and the store beta.
-Store beta is pretty rough, visually. Very clearly a work in progress.
-It doesn't always want to pin the new apps to start screen. Again, just keep trying.
-Outlook mail was a pain to set up, and still doesn't have a good way to notify you about which accounts have new mail. I really really want to have separate tiles for my different accounts.
-Outlook mail no longer has a visual voicemail account by default. I don't know if this is a feature that is still available if you want it. (I like visual voicemail, but not in my outlook app.)
-Office preview apps loaded and run OK, though I haven't done much with them.
-The photos app is completely fixed from build 10052, and is actually pretty nice to use now. Pics show up and get downloaded from Onedrive quickly and easily.
-You still can't share directly from the photos app to Outlook Mail, though you can attach photos from inside the Outlook mail app.
-The keyboard is perfect. On 10052 I kept making a lot of mistakes. I don't know what changed with 10080 (slightly bigger keys?), but it's much better now.
Project Spartan is now the default browser (Cortana search results pop up in Spartan now, not IE), and seems to work pretty well. If you mess up a URL spartan is now smart enough to get you to where you wanted to go most of the time.
-Still gets hung up and needs a restart 1-2 times per day. Just goes with the territory, I guess.
-Battery life is good, probably about the same as with stock 8.1. (Just a seat-of-the-pants guess.)
-Haven't really found any apps that don't work with 10080, though I probably use fewer of them than most.
-Bigger tiles work well, though there are a lot of scaling issues with the live tiles. Looks wierd, but everything works.
-Transparency slider works as advertised and the expanded theme color list is great.
Bottom line: if you don't mind doing some fiddling, try it. The new features for the start screen are pretty cool, and the Office apps are there now.