We have a 2002 Allegro Bus and we have not had any serious problems with the HWH. They do leak a little which amounts to a loose fitting which is an easy fix.
We do have acquaintances that have Atwood Electric and have had to replace them all at different times (2008 Phaeton). HWH is pretty picky about who is their authorized rep but they are just protecting their own product.
Good luck.
Bob