I'll offer up my review. The first time I used this, I dry hopped with pellets for a few days, lifted it out of the beer, put the lid back on, carbed up the keg, then served from it a few days later. There was some fine hop sediment in the beer, and for whatever reason, it did not clear up after pouring multiple pints. I think I was still getting fine sediment all the way to the last pour. My theory is there was just enough turbulence each time beer rushed up the dip tube, that it picked up a scattering of pellet debris in the 1/4" between the dip tube and bottom center of the keg, but never enough to completely clear out the debris.
So next time I got out my Dremel and cut an inch off the keg's dip tube. I filled the dry hopper, dropped it in in a sanitized keg, and racked from the carboy into the keg. No more sediment.
I have not noticed air getting trapped in the lid, thanks to the 1/8" vent hole drilled at the apex of the dome.
I really like being able to agitate the keg periodically to resuspend the dry hops, without worrying about the bulk of the pellet debris escaping the dry hopper. I could just pop the keg in the keezer and serve from it, but I like to get the beer off the hops, so I jumper the beer to a fresh keg. I do the first few oz from a picnic tap, just in case some of the pellet debris makes it out. Once it runs clear, I trade the picnic tap for the jumper hose and push via CO2. I don't even hang the dry hopper when I do this; it just sits on the bottom of the keg, leaning on the dip tube. I lose about a pint at the bottom due to the shortened dip tube, a worthy trade-off IMO.
Just kegged an IIPA with 6 oz dry hop last night. No sediment at all, and I had been shaking the keg twice per day for 4 days.