Nope- no refrigeration, no a/c, none of that. This is a really simple boat- all nav lights are led's, plotter is Raymarine e7D, all instruments are new Raymarine but I do have a power hungry-ish autopilot (my biggest current draw), and I've settled on around 350-400 ah's with a 100w solar panel for cruising/racing as long as a week away from the dock (I know that huge sentence is a run-on and my Mom/Grandmother would not be proud..).
The main reason I like the idea of sealed batteries is for the obvious; they're sealed and I won't have to go through the major headache of redesigning my battery boxes to accommodate a sealed box, that and I *think* (correct me if I'm wrong) they can be drained down 80% from full without killing them occasionally.
If your longest run is one week away from the dock any of the Premium AGM batteries (Lifeline, Odyssey, Northstar, Firefly) should suffice. I would not however take any of them but Firefly to 80% DOD on a regular basis.
The Odyssey can occasionally be cycled to 80% DOD but will have less than half the factory rated cycles of a Firefly when doing so. If you are designing for 80% DOD then your battery options are slim, unless you want to replace them on a regular basis..
6V GC2's are still the best value.. For an AGM I would go Firefly because the cost per Ah and cycle is far less than any of the other AGM batteries.
For example a G31 Firefly vs. an Odyssey based on reasonable usable Ah's looks like this...
Odyssey 100Ah = 50Ah usable for $340.00 = $6.80 per usable Ah
Firefly 110Ah = 88Ah usable for $425.00 = $4.83 per usable Ah
We then have designed cycle life of 1000 cycles to 80% DOD for the Firefly and 400 cycles to 80% for the Odyssey. To equal the 1000 cycle design life with an Odyssey requires discharging the Odyssey to only 65% SOC...
Still the GC2 6V flooded batteries are a significantly less expensive battery...