within brands there are many variations. With the direction of electronics
moving toward integration you may want to look at the various systems to see which has the most for your money
account for a large block of the market.
As far as brand names go I'm not much of a believer in brand loyalty. It would be nice to say one brand was so much better and the people so much more accommodating but it's not really true as far as I can see. You may find local warranty service
to be important since problems do tend to come up right away as often as much later on. This can require a calendar not a stop watch so timing may be a factor for your planned trip.
Good installations are your best insurance
for a long trip that includes long ocean crossings. The details for a really well done installation
are not so easy to pick up on if you've never done it before. I would find the best installer since that is an area where reputation matters most.