I've got it on my daily driver 6S Plus. I like it, it works, so do all my app's that I use all the time. For a major release and a beta 1 it is very good imho. BUT - from advice I read on here and it saved me, turn off automatic iCloud backup's on the phone, as once you backup to iOS 12, you cannot then backup to iOS 11 should you downgrade iOS back. I have done this before. For my daily driver phone, I have found no issues with it. However as you've posted this thread, you clearly have doubts about it.
Developer Betas aren't usually intended for a daily driver if that's what you're wanting to do. If you have a secondary device you could throw it on there and see how it goes. I'd say wait for Public Beta 3 or 4 to put it on your daily driver tho.
I’m so tempted to try it but I’m currently traveling without a laptop so if anything should go wrong I’ll have no way to restore. Better to leave things be for now. But damn just based off the feedback it’s very very tempting.