Quoted:
Put a ACOG on one then try to shoot it from either side like around corners.......you will keep the AR when the swelling from the spent case in your mouth heals.
As MadDogDan said put a Brass Buster on it and no more problems with that.
I am a big propenent of the MSAR/AUG rifles. There are a lot of urban legends about why they aren't as good as conventional layout rifles, but most of those really are just urban legend. A good example is the 'slower to reload' claim- well, instead of grabbing in front of your primary hand you are grabbing behind. You press a button and pull out the mag and insert a new mag- not any slower as long as you have practiced it a bit and know the manual of arms.
In a state like Illinois where SBR's aren't allowed it really shines- I can have a 27" rifle with a 16" barrel without any special paperwork. Need a more compact package for transport? I don't even have to mess with push pins, just remove the quick detach barrel and suddenly it is less than 21" overall.
Bullpups are a growing market, and the aftermarket is finally starting to catch up. For whatever reason there seems to be a bit of prejudice against bullpups, I suspect mostly because they are just plain different from what most people learn to shoot on. But that really kind of captures it- they are not better or worse, just different.
I recently had a Tennessee SWAT officer call and order one of the Brass Buster brass deflector from me, and asked him what he was going to use it for. He told me "well, most my Dept. likes to carry short barrelled AR's. I like the MSAR because we do a lot of house clearing, and I don't have some of the issues that you run into with a short barrled AR- worse ballistics and sometimes cycling issues. A couple of times I have needed a hand free to grab ahold of someone or push them down, and the point of balance on the gun is right at the grip, so I can keep a good hold and control on it. Besides, if I ever got in a situation where I needed to take a shot one handed, it is a lot easier to control than an AR-15." He was buying the brass deflector to solve the one problem with the rifle he had found, which was brass in the face when week hand shooting.
In any case, if you already have 3 AR's, why not sell the mutt and pick up an MSAR or AUG and try it out. It isn't for everyone, but I think it is always good to try something new.
Sven