We have two different threads going on here: GPS and Boat Taxes. My first comment is to the GPS. My government better damn well disable GPS if it feels that a national security threat is real. That Is exactly why Moe had a good comment that even with a GPS unit, you should still have charts for your area on board and be updating your position if you are in bad weather or offshore. The most likely way to loose the GPS is a equipment or battery failure, but at least in my case with a 6 and 7 year old on board, SAFTEY and the ability to get home on plan B or even plan C and D is as important as having the boat in the first place.
On the taxes and this may pi$$ some of you off, but I am just being honest and it was all LEGAL. I was able to take advantage of the OLD california sales tax law that exempted you from sales tax on a vehicle (car/boat/motorhome/RV/Ect) bought out of state and not brought into or used in the state of Ca for 90 days. That saved me about $2000 in Ca sales taxes) . As of October 1st, that law was changed from 90 days to 365 days. Now the Mega-yacht owners will just keep their boat in Mexico for a year (I actually know two people who are doing this to save about $60,000 and $120,000 each on their Mega-yachts, by the way).
At the tender age of 33, I have seen enough in life to realize that the general rules of society often don't apply to those with tons of money. If you have a house in Mexico, France and a few in the US, you will just buy your big ticket items in Mexico and have your captian bring your boat up when needed or fly down on your Gulf4 to use it. No matter how many laws and road blocks that government tries to pass to keep people with big money from avoidng taxes, the people with the big $ are typically smarter than the government (or they contribute to their campaigns and buy them off). Heck I am just a typical upper middle class citizen of this great country, but I was able to figure out a way to buy my boat in Nevada and LEGALLY pay no california state sales tax and save $2000. Now if I can work the system and save $2000, you can bet that when it comes to saving thousands of dollars people will get damn creative.
I have owned a boat for the last 12 years and have never paid any personal tax assessment, not a penny and have always had it DMV registered and I bought it from a dealer, so I don't know what to say about the personal tax issue?

I do suspect that I will not rock the boat

and go looking to pay, but if they find me, then fine they can have more blood money.
Rich