You want to get a mount with micro-adjust functionality. The BEST is the Chief RPMAU. Period. Next up is the Peerless PRG-UNV mount.
Yes, the PRG-UNV has little knobs on it. But, it is slightly looser than the Chief mount.
The RPMAU should be loosened, then aimed 'close' to accurate, then have everything tightened. Then, using any #2 Philips head screwdriver, you can adjust the pan, tilt, and yaw, independently of each other. Even with the projector completely tightened down you can still make those adjustments. It's REALLY nice, because everything is nice and tight. It also has the BEST universal bracket interface on the market. Locks into the projector firmly with near zero flex. Once you use it, you see the massive difference in quality.
Some people swear by the knobs on the Peerless PRG-UNV mount, but the mount does require things to be slightly loose when those are adjusted. While Chief can be fully tightened, then have micro adjustments made.
Plus, if you have the projector mount tight to the ceiling, you can use a longer screwdriver to make the adjustments if you need to. If you have plenty of room between the ceiling and the mount, you can use a stubby screwdriver instead. So, it's more flexible in how you choose to make adjustments.
I went through testing of about a half dozen different mounts many years ago. I've also use another half dozen or so over the years, and I keep coming back to the Chief RPMAU mount. The Peerless was the one that held its own against the Chief though. It was a strong second place finisher.
I buy my Chief mounts on eBay, almost always used. I can typically find some combination that can get me what I need for under $100. I'm also willing to just grab any projector interface bracket and cut some new holes in it so it fits whatever projector I'm using at the time to save a few bucks and have a 'custom' bracket for the projector in use.
