I have used this 18" wrench for over 15 years, building and disassembling chemical loading systems of galvanized pipe. Mine has a little less paint on it, but the jaws are still sharp. The jaws are replacable, but I've never had to do that. I have also used this wrench for home plumbing projects, but it is a little large when working in a sink cabinet. I use it mainly as a "holder" in that duty, turning the fittings with a 10" wrench.
Rigid wrenches will not fail you if you give them a little respect!
I have never had any problems with them (I own 2 of them) and have done just about everything with them. If you have to use them a lot it won't take long to notice how much easier it is to do a job when your tools aren't weighing you down. If you need 18" pipe wrenches give these some serious consideration.