I thought I'd give an update on what I decided to do. (I already tried
to post this once, but for whatever reason, my post never made it
through).

First of all, a huge THANK YOU for all of your replies, ideas, and
discussion.

I decided to go to Sears and buy the dual power unit. It has a .95
effeciency rating, which is a few points better than the ones Lowes and
Homer Depot carry in my area.

I confirmed in the store what I was told by their reps on the phone-
the bottom element can run at 3800 or 5500 watts. The top one is
always 3800 watts.

Converting the bottom element back and forth between 3800 and 5500
simply involves adding or removing a metal "bridge plate" (i think they
call it a buss) from the bottom element. It comes from the factory w/o
the plate attached = 3800 watt. When you add the plate it bridges two
connections on the bottom element = 5500 watt.

I don't know a lot about water heaters, but I think most elements only
have two connections- this one has three, and when you bridge the two,
you get 5500 watts.

So, during the 99.9% of the time when I am not running on generator
power, I get better performance and during the .1% of the time when we
might be out long enough to want some hot water, I can convert wattage
w/o doing anything that 1) voids the factory warranty (ok, who knows if
running on generator power might void the warranty too LOL) and 2)
makes a big watery mess.

Anyhow, I don't have it in yet, as I'm waiting for a friend to help me
on a weekend, but it's sitting in my basement ready to go.

Thanks again for all of your help!!!