For the same amount of money you could pick up any number of tanks and either double them up yourself or, maybe, get them dubbed as you buy them. For the price you could potentially find a set of HP100s, singled or doubled, and have twice the gas without much of an extra weight penalty.
My problem with those cylinders is that while you do have the redundancy of manifolded doubles, you don't get the extra volume of bigger cylinders. I'd personally rather dive a single LP95 that still has it's plus rating, even with a hot fill you would have almost the same amount of gas entering the water. That way it would work with your singles rig without being so Frankenstein, thus introducing a degree of risk if/when your wing gets pinched.
Keep an eye on Craigslist, Ebay, and the classifieds here. If you are in Atlanta you have a HUGE cave/tech community just south of you and I'm sure you could pick up some tanks for a deal. Heck, I found a pair of LP95s doubled here in Hawaii where technical diving is fairly uncommon for half the price of that set, current hydro and vis. I broke them down into singles and they are now my main tanks when I go diving.
Peace,
Greg