I’ve also compared both at the same time, and my findings were the same as above, only 1-2 FPS difference between the units.
The V3 is rock solid and for one rifle, perfectly fine, but becomes a huge pain, of you have more then one rifle, a switch barrel gun, or want shooting buddies to use it on the same range day. Then the LBR crushes the V3.
I have had my LBR from the first possible day you could buy them years ago, and it hasn’t missed a beat in many many thousands of rounds. It does potentially take a little while to learn where and how to set it up, but once you have that figured out, it’s so easy to use, with an accessory battery pack, I could never go back to the V3.