OK I had a quick chat with Mike and he was very helpful as usual (I love this company 

).
The MPS-1 plugs directly into 
any BP25, even the old ones that came with the AC supply.  The MPS-1 is not necessarily plug & play with any BP20 however.
So Werd: I wonder can we make a deal for your MPS-1?  Maybe I have something you might want to trade for?  Send me a PM.