Thanks to everyone for the replies. The Watts In-Line is a nice streamlined tank. It was, I believe, introduced in 2003, so I was surprised to learn they'd discontinued it. I know I'll have to replace it eventually with a standard type, but thought if I could find one somewhere I'd just swap it out now and put the replumb job on the list of things to do in the future. Guess the future is now! Again, thanks for the replies.