I have no experience with dampa mount. But my HW90 works great with the RWS lockdown droop compensated, and the Bkl one piece mount droop comp. Note, the RWS mount will not fit an Airmax scope.
Cocking effort is a little high, but not too bad. Only one arm needed at 20 bar. Unlike 26 bar, which requires two arms. 💪😁💪 Noise wise, my neighbor says he can barely hear it. The accuracy at 20 bar is very impressive.
My hw90 issues are resolved. I recently received it back from AoA for a broken stock weld on the cylinder. AoA replaced the cylinder under warranty. A shout out to AoA for great customer service. They set the pressure at 20 bar. Six shots at 20 yards. Squirrels beware. 😁
I stripped down my HW90 to replace the piston seal and found one of the front stock tabs completely broken off from the cylinder (no wonder it was shooting poorly). Can the tab be welded or jb welded back on?
This discussion is super helpful. Recently my HW90 has been shooting poorly. I am going to replace my seal with a Vortek vacseal next week. Fingers crossed.