The At Pro is terrific. You'll find tons with the AT Pro almost anywhere you use it. Plenty of evidence online and happy users to prove it.
It's a fantastic all around machine, and definitely a great affordable relic machine. The AT pro pinpoints like a dream, and it has really, really nuanced, descriptive audio once you learn its language. You need those features for relic hunting and you're not going to get them out of most inexpensive detectors. (The AT Max audio is different and I don't care much for it.)
With the 5x8 coil in the woods it's really easy to maneuver close to trees and objects, you can practically throw it and not break it, it's "deep enough", and those areas usually aren't all that trashy anyway. Throw on the standard coil for a bit more depth or get a third party large coil for the fields.
Yes, there are better choices if you're going to hunt saltwater or if you want to squeeze every coin or ring out of a site. I added an Equinox 800 because that's what I'm trying to do. So far it's not disappointing me. But, I'm also keeping the AT Pro around to mix things up, to use it in the woods, and for quick clad cherry picking hunts. In fact, if I could only have one detector I'd have a hard time choosing between the two. The AT Pro is more than enough detector for most dirt hunters.