So I started my PCP adventure with the Umarex Origin .22 and thought I would offer a few observations for beginners like me.
The rifle package with a hand pump was the deciding factor. Easy to try out PCP shooting for less than $300. Shoots better than I do and, once I understood the "two plateau" velocity range, I found that I can get 20 consistent shots from 2400 to 1800 psi with the hammer spring at minimum for 850 fps, and then about 35 pumps to be ready for another go.
CPHP - These are amazing! $7 for a tin of 500 at the Walmart, and this rifle loves them. Consistent groups of 1/4 to 1/2 inch at 30 yards. The limiting factor here is me. Oh, Crossman Premier Hollow Point. Oh and targets are in stationary, not sporting goods. Post-its, binder reinforcers, 3/4" round labels - almost free. And if you have a particularly noteworthy group, just pull the post-it and put it in your notebook.
O-ring Delete - tried this out, replacing the pellet probe o-rings with a snip of fuel line. Reduced standard deviation for a 20-shot string from 12 to 7.
Complaints - only 2. The scope rail doesn't line up very well with the barrel. Had to shim both rings and base to have any clicks left at all in either windage or elevation. And the comb is a bit low once a scope is mounted high enough not to interfere with the magazines.
I think I may be hooked.