I've finally decided to upgrade my scope. The Millet 4-16x50 TRS-1 was OK for the $$$, but I wanted more power and better tracking.
After a ton of research, I decided on a Vortex Viper 6-24x50 PST. I wasn't sure about the busy PST reticle, but once I realized it was MOA vs. Mill Dot, I was OK with it. The other reason for going with the PST was the huge dimensional differences between it and the standard Viper 6-24x50PA. That's really an issue for me as I need a long eye relief scope to avoid having to mount it too far back.
I'm not sure why the reticle choice makes a difference in the eye relief, but it does. PST = 4", Viper = 3.2", unless I'm missing some other difference between the two.

Anyway, it's on the way.