Hybrid water heaters

What are your thoughts pertaining to hybrid water heaters.

http://www.eternalwaterheater.com/catalog.php

The price on the units are $2499 and $2799 if anybody cares.

Supposedly they are 35-40% more efficient then a typical tank.

They came out in 2006. I would expect someone has or will come across these in a high end house.

The printable document has most of the information if you were to ever see a hybrid water heater.

I have been thinking of upgrading my water heater for a more efficient type, but the price on that hybrid is way too much.

AO Smith has a 90% efficient one, but there is no local dealer here. Plus it is a 50 gallon unit, which is bigger than I need/want.

I was surprised how low the efficiency is on the regular water heaters.