Buy once, cry once - Wilcox G24 Mount w/ Low Profile Breakaway Base

It's hard to think that a hunk of metal smaller than the size of your fist can be worth $500 (on a good day), but let me assure you, it's worth every penny. The machining quality is surpassed only by the functionality and adjustability of this unit. I have had very little experience under NZG's until recently, but the ability to adjust your goggles to your face, and at the right angles is most certainly paramount, and this unit does not fail. Don't waste your money on a cheap knock-off. You'll end up back here anyway.