I was a little apprehensive about the OME X-HD coils, but it turned out GREAT! The pre-coil swap height of the hitch (for reference) was 19 1/4" and 21 1/8" after the swap. So I gained almost 2"! I figure it'll settle some, but I've very happy. I'll have to take pics.
BTW, I also installed some JKS rear axle spring mounts. It helped that the OME coils are thinner -- the FT coils might have rubbed the gas tank after I'd realigned the spring mounts... The downside is I couldn't re-use my air bags - too wide for the OME coils. I'll have to find some thinner ones...
As for the batteries... My alarm system has been going off on it's own recently -- something I have to check today -- and since my Hella horns take so much juice, I've noticed my starter battery went down under 12v recently. I was quite pleased to know that I had my second battery for a boost if ever the alarm _realy_ went nuts and drained my starter battery...
In the long term, I plan on adding some solar panels to the roof rack...
js.