@edevlin - Thanks for the info, it's a big help.
@heyjae - Thanks. I read that Braille batteries are just repackaged Dekas too - the VW guys swear by them. I read that using many of these batteries without changing the alternator's voltage regulator will constantly overcharge them. Swapping the voltage regulator on the Bosch alternator is easy - it's just a snap-in modular unit.
@Kirk - I agree. But, I have read that the use of a Cap is unecessary and actually further increases the draw on the Battery/Alternator.
Essentially, the article said, that the Cap discharges some energy to meet the demands of the amplifier, but then recharges itself immediately, adding to the strain already placed on the battery to begin with. The guy who produced the 1st Car Audio Caps is now advising against their use for that reason.
Most high-end Audiophiles now use additional batteries and/or custom alternators with increased capacity. There are also devices for sale which allow two batteries to be used, but cut one battery out if the draw becomes too great in order to protect it for car starting, accessory power demands and such.
Space in the Boxster is limited, so I think a custom higher capacity alternator has more appeal and practicality than either additional batteries or Caps.
But, I better be careful here or I may incur the wrath of
Jack G... j/k Jack