I bit the bullet about 6 months ago, and replaced my poly plastic QD's with the MoreBeer Stainless Ball-lock style QD's.
They cost a small fortune, but for durability, flowrate, and ease of use, they can't be beat. I have no regrets about the purchase.
I used 1/2" MNPT x male QD on all of my vessels (valves, pumps, chiller, etc.) and used 1/2" Barb x fem QD on all of my hoses. That method allows one handed operation to connect/disconnect.