Carbon Capacitors?

Greetings all,

I've been out of the Car Stereo game for awhile, but am starting to put things together for my )5 F350 when it arrives. 

Back in my day, you were tuff stuff if you had 1 or 2 1-farad caps.  Now, I am seeing a 40-farad cap (lightning audio, among others), that seems incredibly low priced for what it is.  Am I missing something here?  Are these things not all they are cracked up to be?  I note that the normal 'can-shaped' caps haven't really changed in price much, so what gives on these larger ones?

I am aware that Alternator comes first.  I am beginning to order parts for my recently order 2005 F350 Lariat 6.0 PSD.  It will have Dual, 130-amp alternators.  Since the truck can run comfortably on just one of those 130's, I figure that leaves me 130-amps or so to work with.  I don't figure I need any extra batteries, as I am not looking for run time in the parking lot.  I'm not showing off to my baggy pants friends 'Cause, well, I don't have any.  Picture Hank Hill.  Yeah, that's me.  I am married with children, but still like some Offspring or AFI now and then.

Anyway, I previously have had 2 1-farad caps that have traveled with me in all of my cars over the years (had them since I graduated high school in '93).  At the time, I had a little four-banger, and definately noticed the difference.  When my Phoenix Gold MPS2500 hits, it draws quite a bit of current.  I know my new truck will have enough amperage to power my system, but I figured more can't hurt.  I will eventually have some hillbilly offroad lights, an air compressor (for air horns, air tools, etc), and all of that stuff needs electrons too. I want to be able to winch my buddies Dakota out of a ditch, air up my tires with the compressor, give somebody a tan with my spotlamps, and jam some Pennywise all at the same time.  Is that too much to ask?

Lastly, getting back to my original question, it struck me as odd that 1-farad caps are still $60-120, but a 40-farad is $200.  I know the old adage of 'you get what you pay for' and 'if it seems to good to be true...', but I was hoping for some insight into the actual nuts and bolts of these things.  I am sure I am not the first one to remark at how the pricing is odd, if it truly is apples to apples.

But that's just it, they are made by LIghtning Audio / Rockford Fosgate.  If they had been Rockwood or Pyramid I would agree. (are they still around, or am I dating myself?)

My thinking was like this:

I was going to purchase two 1-farad caps.  It's what I had before, I figured I would have it again.  (sold them with the old truck, it was part of the deal).  But when I figured it would cost me about $200 to replace them, I started looking at these 40-farad deals.  It seemed too good to be true, but with the Fosgate name on them, I figured they couldn't be total garbage, right?

The Ford Deisels all have two batteries stock (it needs that much CCA for starting, apparently).  I was always of the understanding that extra batteries for a stereo were all about extended run time when the alternator isn't turning.  Has this mindset changed?  I know I have plenty of source amperage for my system, it's just a matter of how quickly the alternators and batteries can respond, right?

Also, some additional information.  I contacted Phoenix Gold regarding my trusty MPS2500, to have them confirm what it is truly capable of before I go buying my new subs.  They advised a minimum 1-farad cap if I run it at 2ohm or less (which I probably will be).  If caps are a myth, they seem to be buying into it too? 

http://www.sounddomain.com/item/PHOTIMX10K

Sure they are.  They have the product for sale, too.