Ah. If you've got an aftermarket hop unit (which you'll probably want for the better seal a lot of them give) then you'll want an AEG barrel anyway - the ability to R-hop is nice.
I have the AA hop chamber in both builds currently. The only hop unit I know that takes AEG's is the PDI and the Airsoft-Pro clone, having owned PDI hop's before, they sucked balls.
I had a PDI in my L96 and it wasn't brilliant. Worked ok with their W-hold but yeh. I have the AA one in my SDiK right now and it certainly works with AEG barrels and buckings. I actually put a Mapleleaf VSR bucking on and it seems to work ok with that too, which it probably shouldn't. I was going to buy another 6.23 for it but went for the ORGA 6.13 in the end to see what it was like.
I ran the Prometheus flat nub with the Maple Leaf as people said it would work fine, but I did need to file out the hop window in the unit a little (not sure why they made it so damn small). Will certainly be R-hopping over the weekend though as my material just arrived for it.
Just to clarify, as I think I've misread. You have an action army hop unit (bright red one) and you've ran it with both AEG barrels and buckings, plus VSR buckings/barrels?
I got the AA (bright red) unit. I tried an AA AEG barrel and the ORGA barrel (both AEG) and used both with a VSR and AEG bucking. Both work well. Some people have been using the W-hold buckings from PDI too (which are AEG buckings as you know).
I've got 2 builds on the go fella, a Gspec which will be <350 so I can use it everywhere. Plus an SPR which will be <500. How much would you let the orga go for, I might just out the SPR outer on the Gspec as I have the fluted on the SPR, that way I can fun it into a supressor