[EricE]

Electric is crazy expensive to just about anything else unless you live in an area subsidized by cheap hydro power.

Loops in new construction are out of synthetic pipes that are one continuous piece - no joints other than at the manifolds. Most systems have the pipes installed in concrete (yes, there is lightweight concrete for floors with wood joists; I've considered it) so unless you are deliberately stupid you aren't going to puncture the piping. Water in the system also counts towards the systems overall thermal mass to, helping keep the heat consistent.

Since few people seem to experience radiant heat it's pretty hard to state just how different it is and feels. It's amazingly comfortable.