If your pipes are getting old, might want to look into PEX pipes as well as replacement. You can run dedicated pipes to each outlet straight from a "splitter" manifold by the water heater. It cuts down on sounds of water going through pipes (that THUNK you sometimes hear is water hitting the metal piping when it starts/stops flowing). It'll also mean no one will ever cut your hot/cold water in the shower by turning on a sink or flushing a toilet or whatever.

Since they're flexible, you can run them through the attic and need very minimal work compared to replacing with new copper piping. (At some point pipes have to be replaced, too, just like wiring)

(http://www.autoadmit.com/thread.php?thread_id=4595663&forum_id=2#40691001)

but unless u need the extra space i prefer tank-based water heaters (preferably indirect water heaters)

tank-based water heaters provide uniform hot water flow, and are simple and therefore easy to service / maintain. tankless water heaters are more complex and likely require quite of bit of maintenance.

(http://www.autoadmit.com/thread.php?thread_id=4595663&forum_id=2#40691698)

edit: was this magnum model ultra expensive?

(http://www.autoadmit.com/thread.php?thread_id=4595663&forum_id=2#40691731)