here's the deal with panel frames. If you double roll the mesh, you only do one side, not all 4. That will bring them up into the high teens. You can only double roll after you printed on them a few times or it will bust. at first tension, they are like Mike said in the mid teens. The main issues we have is the powder coating is coming off and turning into a real rough almost sandpaper type finish. When stretching a panel, we can get all the way to the end of the frame and the locking bar starts to do a 90 degree turn up, not sliding down and locking into position. we ripped about 3 305's the other day trying to get one frame to work. The tiny holes, we get those too. I believe they are pressure points put on the frame inside the frame holders on the press. we don't use frame tape and panels, so I think that's the issue there.
I am / have been slowly switching to rollers, it's a little more work but it's night and day as far as a print goes. I wish I would have listened to Sam and went with them sooner.