bglazio - curious as to why you don't use the internal batteries? Thanks
A few reasons. I already had the WalMart battery and Kind Kables power cable from my previous UA-5 and then R-4. That cable is the correct size for the AERCO (polarity does not matter for the AERCO).
I don't have any 9V rechargables, and don't want to purchase new 9Vs every couple of shows (or worry about whether they are fresh enough).
Plus, it's easier not to have to open the case up.
I'm running open, not stealth, so the extra size of the WalMart battery works fine. I get all my gear in a nice little Lowepro Nova 4.