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Watts up in the house?

If you were me, and all else were equal(ized)...

Plenty of ab crunches in my future if this is the way forward.
Can't resist a good electrics pun, I'm afraid.

I've posted this query on Cruisers' Forum, but it struck me that I have a fairly experienced readership right here, so why not ask?

Let's assume I wish to make a six-battery, roughly 1100 Ah house bank. Assume I have all my charge sources sized correctly and adequately, and I have all the space I require close to the boat's CG. Assume I like Trojan products and the tall L16 form factor, although this is not a must-have if I can save a few hundred with an equivalent battery maker.

Would there be a case to favour six 2V batteries to form one big bank using this model of Trojan L16: Trojan L-16-RE-2V 2V, 1110AH (20HR) Premium Line Flooded Battery

or to go series/parallel with three pairs of 6V batteries of this model? Trojan Battery Company

The rationale for hooking together a bunch of massive two-volters is found here:

End result is the same, and I gather the 2Vs are more robust in terms of plate thicknesses and general construction, but if one of the 6Vs went bad, would I not have the ability to remove its partner and simply fall back to a house bank 2/3rds (two pair instead of three) the intended size?

I've got a feeling some of you could provide real-life-based guidance here. It's akin to those compartmentalized batteries Rolls sells, only via a different methodology. Thanks.

Oh, and for the curious, I would keep the separate 12 VDC start and windlass batteries (probably Group 27s) charged via echo charging from this house bank. The charge sources, mentioned here before, include four 135 W solar panels, a 400W wind generator, and one 180 amp alternator or two 75-90 amp alternators, switchable to charge either house (default) or start batteries.

UPDATE 14.06.05: Have yet to hear back from the Ceol Mor's perfectionist skipper, but collected wisdom is favouring the "three pairs of 6VDC batteries" option. Now I have to shop as concepts such as "core charge"  and the vagaries of buying in Canada versus in the States (shipping, HST, yadda yadda) strongly affect the end prices of each battery. Seriously, there are significant price differences that don't appear to be related to battery format or Ah capacity. I'm a bit off the Trojans now, as I've been persuaded that the "quality gap" has been largely closed and you're paying for the name...for which I don't care to do. So I'm pricing these U.S. Battery L16s and these Interstates. And I'm trying to find some old dead batteries to offset the prices I find if I buy here in Canada. Thanks to Jeff C. for some leads.