I've used Leupolds for years and had good luck with their products. I have several older VX II and VX III scopes, a couple newer VX 3 scopes and now 4 of the VX-6 scopes. I never had issues with Leupold until I started using the CDS system and dialing regularly.
I have three of the 3-18x VX-6 scopes with the TMOA reticle. I love the glass, reticle, everything about them except the tracking. I have issues with consistent return to zero on my 25-06 and my 264 win mag. Both these rifles have been accurate out to 600yds with the scopes they previously had, a Vortex 4-16x44 and a Swaro Z5 3.5-18x44. I installed one of the Leupolds I've had issues with and my gunsmith installed the other, so I don't think it was an issue there. I have a Wheeler kit with to lap rings and mount and level scopes. I use the torq wrench to make sure the screws are the right tension.
Both these scopes hold their zero fine if I zero them, tap the turrets several times with an empty case, re-check the zero with a final shot, and leave them alone. It's only when I dial elevation that I have issues. I use these scopes for hunting and I don't want to wound an animal due to an issue. If I ever have to take a follow up shot at a different range I don't want to have to stop and thump my scope before shooting after adjusting the CDS. I'm sure Leupold will make it right when I send them in, I hope they have improved the CDS on the new HD series of scopes. I sure like the reticle and field of view. The other two VX-6 scopes I have I just put on rifles I don't dial and they have been great if I just don't use the CDS and treat them like they don't have it.