I use one piece mounts on all of my springers, I prefer Sportsmatch over BKL's and use them on my HW Rifles. My Diana's all have barrel droop, so besides the adjustable mounts which I tried and did not care for, that only leaves the RWS/Diana mounts and BKL's that I am aware of? I use the one piece BKL Droop mount for my Diana's, along with blue loctite on all the bolt threads and 3m friction tape on the scope rings. I will probably try the Bullseye at some point, seems the reviews were getting better with the newer versions, but I have not researched that as of late.