Dear Cheryl, Jay & all: (Thanks for remembering me Jay) Cheryl, it's difficult for me not to be biased or prejudiced in favour of tankless water heaters, I've been involved with them in one way or another for over thirty years. I was first, a user, then installer and finally in the marketing of them. So I got into this business, because I truly believe in the tankless concept. Also, over 90% of the domestic hot water in Europe is heated with tankless water heaters, and has been for a long time. There are many reasons for this, but the main one is efficiency and low cost of operation (energy costs are far higher than here, I'm originally from England, where gasoline presently costs almost $6/gal). Tankless heaters are more reliable and last longer because are in operation a lot less often than tank heaters; they only come "on" when you ask them for hot water. Tankless heaters don't accumulate mineral sediment on the bottom, because they don't store hot water and don't have a "bottom". And if mineral scale ever does become evident, it's very, very easy to remove. (I've never had to do it, but the procedure is extremely simple) I'm not sure what the original reasons were for developing this type heater, but the benefits are now undeniable. 1. Instant, endless hot water. 2. Very space saving. 3. Cost less to operate. 4. Last longer (20-30yrs) and every part of every unit, can be replaced without throwing the whole thing out by the roadside. I have never, ever, seen an AquaStar, Seisco, T-K1 or Powerstream laying beside anyones trash! Sorry Cheryl, I realise I don't meet part of your criteria...I'm terribly biased toward tankless water heaters and always will be. If you need to know more about them, please let me know and I'll e-mail you info or you can call me at 1 800 851 9891. Sincerely, Brian(tankless)Wood.