If price is an issue, Fechter pointed this out a long time ago, you can use a lot of your laptop/printer/etc power supplies as a dc/dc converter. A lot of them will run off <110v (some don't so you have to check the ones you have.) But I'm sure a lot of you have some extra ones just laying around from past equipment, I know I had a bunch and I tested them out on a 48v test pack that I setup. The output on them also ranges from unit to unit, so check that also, but they are free, so you can't really beat that. Just thought I would throw that back out there.
Johnson64.Com "The stone age didn't end because we ran out of stones."
'13 Zero S 11.4kwh
GS500, ME0913, Sevcon Size 6 Controller, 90v40ah Lipo, GSXR suspension.
'87 Hurricane 600, ME0709, 48v/50a SLA, Kelly KD72400, Magura Throttle, High Current Cycle Analyst
Raleigh beach cruiser: 9C rear hub, stock controller, 48v10ah lithium, Cycle Analyst
Phat Chopper: 9C front hub, stock controller, 48v12ah a123s, Cycle Analyst