Blue Sea Systems
I purchased numerous Blue Sea components (3 panels, bus bars, fuse boxes, etc etc) for a rewire this year. Everything worked fine except for the 2 hydrosonic water tank monitors; one always read empty, one always full. I tried the differenct calibration procedures, did some testing with a voltmeter etc. and finally called their tech support. They couldn't have been more helpful, I was in email contact with 2 of their engineers who shipped me 2 new sensors that they had tested which cured the problem.
During the first call with one of the engineers, before I got off the phone he said "listen, I just want you to know that we will stick you until this gets resolved even if it means replacing every component in the system" (he was referring to the VSM 422 monitor).
Top notch products which they stand behind all the way.