Yes I've put several arrows into it already. They penetrated out the back about 5" with the 50# bow at 20 yards. With the 35# bow at 35 yards, just the point and maybe an inch of shaft was visible on the back.
There was no damage to the arrows. The rubber slowed them down and stopped them without any apparent shock. The rubber grips the arrow pretty good, but no trouble pulling them out with a little side-to-side pulling.
I'll get some pics, but not today. Windy here today.
I used the swingset brackets from my steel rifle target, and conduit tubing. Secured the mat to the top tube with zip ties every six inches.
No problem. I finally found a few pics of how others did about the same as you. I'm going to use saw horse brackets and treat 2x4's for hanging the stall mat.
I'm shooting a ton and working on form. I get the magical group of 6 and then a shotgun splatter on the next end. Once I get a tad more consistent I'll back up to 20 or 25 yards. Don't won't loose a bunch of arrows.