Just to add to this, I just picked up a 407CO and threw it on a G45, and absolutely love the reticle/donut too. Unfortunately I'm largely limited to dry fire and the coolfire trainer outside of matches since my range is now 90 min away, but I really like this optic. Mike Pannone told me that he thinks the 407 series is the best optic for the money available and he has over 20k on 1 of his Holosuns. He reports that his have all been solid.
I zeroed the new 512 on a MPX PCC today and really liked it. Prefer it to a green 510.
Likes pretty much everything in every caliber.
Well now you have me second guessing. I was all set to buy the hs or he 510 for my pcc...
Well screw it. This guy has them with a $50 off coupon so I ordered a 512
https://www.heartoftexasarmory.com/s..._HS512C.html#/