Personally, I feel the QR is more novel than anything else.
The QR is a great feature in my opinion. My keys are always with me so now my Beta QR is always with me. For extended use, I prefer to not hold my entire key ring. With the QR feature I don't have to fumble with a split ring. If you like to pocket carry a light every day, I could see the QR being an unneeded feature, but for me it is one of the reasons I bought the light. Sure you can use a QR on any keychain light, but the female end being built in really helps reduce key ring bulk.