I have an older Ripcord and found that I could not use it on two of my bows (Martin Cheetah and Firecat). I suspect it was too slow and I was getting fletching contact, A call to Ripcord pretty much confirmed that. They told me to send it in and have it looked at. I put it on a slower bow and it works fine.
As for the QAD I am not sure. What kind of adjustment does this rest have? The NAP Apache has toolless adjustment both vertically and horizontally and the entire unit sets behind the riser rather than over it. This gives you the ability to shoot a shorter arrow.