I'm considering connecting directly to a 12 volt power source such as a large 12 volt battery (connected to an ac/dc charger) or directly to a high amp ac/dc converter.
The Dell DA1 is a 12V 150W high-quality power brick (< $10 on eBay) that will more than suffice for the job.
Further you can easily mod it to vary the voltage from 3.7V-12V, see
here and
here and
here.
It will also work fine when hot-plugging devices with big inrush current (unlike its big brother DA2 18A/216W)
For more power consider server supplies, e.g. for a few dollars more you can get a very compact 47A 575W HP DPS-600, connect it to a power distrubution box and power all of your 12V devices (and it is
quiet if you do the fan mod - much quieter than the Opus fan; it doesn't start ramping up till around 17A).
All are very high quality - made by top-tier manufacturers (Delta, Flextronics, or Lite-on depending on rev.)