Three or four years ago, I had the exact same questions. I excluded the "HOT WATER ON DEMAND" units, for the reasons listed in this thread. What I did was install a Reem Marathon MR105245 electric HWH. It is garanteed for Life! Heres the link....
This link is broken, either the page no longer exists or there is some other issue like a typo.
We paid about $600 for it. It is a Special-Order item, right from Home Depot!
105 Gallons of hot water. NICE! I think theres 4 inches of molded insulation to make sure it remains hot. Its on a timer, so this allows us to not heat water during PEAK hours, the hotwater only gets heated at night during OFF-PEAK hours, cuz our electric Comp charges different rates. We love it! Savings was about $20 a month over our previous generic 50 gal electric HWH.
Edit: This HWH must be popular.... the price has DOUBLED since we bought it
Edit: Heres some pics....