I tried it at RC1 and RC2 on my Pixel 2, but too many of the apps I use every day haven't been modified to run on it yet, so I want back to Pie. Is it a major improvement? No. It's more of the same. Some changes, some things will take getting used to, but not like going from Cupcake to Pie.
(If you do decide to try it, make sure that there's a "return to Pie" path for the OP, and use that path to try it. On the Pixel you can join the program and get the update. Then if you leave the update, you lose all user data, so if you don't have TWRP installed, and make a full data backup first (and that includes Tipatch, so you back up your sdcard folder), you have a problem.)
You can also, at least on the Pixel, download the Q update file and update to it manually - but there are now two problems. One - the PC no longer sees the phone, so you can't flash Pie back to it (which, thanks to XDA poster somin.n, can be fixed so trivially I hate myself for not discovering it) and you lose all your data and have to restore from the TWRP backup you made before you tried Q. (Or make another backup before reverting back to Pie if you've made changes you'd like to keep after reverting.)
I'll wait for the official release, by which time those apps I use should have been updated.