One of the best drop aways made, but would put Rip Cord, and Limb Driver, as well as Trophy Taker right there with them ! Just depends on what your looking for in a rest !
True they do at times have some tuning issues, as with any drop away, and some claim to have fletching contact with them, BUT I have never had a issue with the hundreds I have set up, and would say most of the tuning issues is due to improper set-up, and timing the rest.
You will be pleased with the QAD, and yes the feautre that allows the rest to stay up on let-down is nice ! If you dont have the money for the HD, take a look at the Rip Cord, they are also a High quality drop away, and has all metal parts ! No plastic in them unlike QAD.
But any of the above mentioned rest will serve you extremley well !
Good Luck with your choice !