Has anyone used and Eberspaecher, Hydroni 4 coolant heater? see attached link for heater info. Fairly pricey!! around $ 1200 Cdn. However I think it would be a great addition for my TDI, for the cold Canadian winters.
http://www.espar.com/htm/Specs/water/D4Wspec.htm
http://www.espar.com/htm/Specs/water/D4Wspec.htm