[C320-list] Batteries

[Scott Westwood]

OK.  Another loaded question:
I am trying to dig into the decision to replace the existing battery(ies) or switch to AGM.  One of my Liquid Batteries is toast and needs to be replaced.
AGM batteries are more than twice the price and it will "likely" mean replacing my existing charger.  I need to verify that but I am assuming, for now, that I will need to replace the charger I just installed 3 years ago.
I understand the value of non-liquid AGMs and not having to keep re-filling distilled water, heeling not an issue, etc....
If I go ahead and go to AGM and replace my charger, then I might as well go ahead and get an upgraded monitoring system.  Right now I have the old analog rocker switch and I would go/add a digital one that would show the current load.  I always like the thought of knowing how much current you are drawing "right now".  I added a remote panel monitor for the charger when I replaced it so I have some sort of monitor but would be nice to know current draw.
A co-sailor is suggesting I move to the West Marine 4D  at $790 each... while I can replace the existing liquid LA for $280 each and keep my charger.
Does anybody have any experience with longevity of the AGMs?  If they live twice as long it might be worth it to do it all now.  If not then I don't see the value.  I can replace these LA batteries every 5+ years and save boat units.
May even think about adding a start battery??
Any thoughts out there?  Has anybody re-done all this and have models/pics/experices etc....  Projects on the website?
I said it was a loaded question(s). 
Thanks,
Scott Westwood scottwestwood at bellsouth.net H (919)-362-8538    C (919)-618-7185