I went with this on mine, but I scored it at a considerably better price:
http://www.opticsplanet.com/vortex-optics-viper-hs-2-5-10x44-30mm-tube-water-proof-rifle-scopes.html
and I went with this for my wife's grendel. again, I got it on sale at a far better price:
https://www.amazon.com/gp/product/B006YVT0R8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
so far I like both scopes.
