The Onyx 230? It looks like it's more than what I would need. The only down side is only 3s lipo/A123. So if I decide to step up to a Maxx or an 1/8 conversion (more along the lines of "when" actually- just can't afford it right now), then the charger would be obsolete.
Does the MRC 989 do A123s? That's a charger I've always drooled over ever since it came out....
I've seen the "dapter". It's a great idea, but it doesn't charge to 100% (which probably will extend the lifetime of the batteries), so that bugs me a bit. I would personally rather the batteries take in their full rated capacity as opposed to a fraction; especially if it's a larger pack (I mean, I am paying for all the capacity, so I might as well use it....lol).