Does not heat water. Installation same as any other. Hardest part will be dealing with the fuel pickup. You need to get a pickup to the tank. Some have put them on the fuel pump assembly, others have drilled a hole in the tank and installed. Gas fumes are dangerous so drills and such are dangerous around them. Read up on that if you intend to DIY that portion.
Install is not that bad, just takes planning as you have an intake, exhaust and fuel line on the outside. Mine works great. I suspect it is not more or less reliable than the diesel versions, maybe more so since gas burns cleaner, but that is speculation. A B4 would keep that fixed top very toasty.
Tim - 2013 EB V10 Agile 4x4 SMB PH Ginger Army All Terrain Mobile HQ