I have bad mouthed my ST6001 several times here as it has given me lots of problems. Raymarine and I have gone back and forth looking for a fix, but I have not been able to use it for the last two seasons. We would get it fixed, but then it would quite working a few days later. It was finally determined to either be the rudder sensor or the computer, but both tested out fine. They even sent me a new sensor which worked for a couple of days, but then the computer couldn't locate it. Finally, I decided the problem must be an intermittent one in the computer and decided to just by a new computer for $600. Before laying down the money I wrote Raymarine asking them if they might give me a discount on a new one. They would not, but are instead just giving me a new one. It is out of warranty, but they are still going to replace it free of charge.