I've got the 4.5-30x50. It works just fine. The turrets work very well. I've had no problem spinning them to get beyond 1k.
I wish I would have waited for the tactical turrets that are coming out, but it works good.
I was at Benchmark barrels today checking up on a build I have in work and Ron (owner) let me take a peek thru his 4.5-30x50 scope. Stepped outside with his 375-Cheytec monster rifle and I was pretty impressed with the optics. Looked out acrossed the farming fields 1500 yds or so into the trees and brush at 30x. The optics seemed pretty clean considering that I just panned from 4.5x up to 30x - amazing in fact.
I am curious Geargrinder, what do you have your scope mounted on?
I am having a 300 RUM built and concerned about how well it will hold up.