[David M]

I think you also have to take into consideration that marine electronics manufacturers who manufacture integrated systems, such as Raymarine or Furuno, have no financial incentive to make their electronics compatible with their competitors electronics. I think that waiting for any sort of standardization that would increase interoperability would be pointless.

I think the best that can be done is to buy the integrated system and then buy a very basic standalone backup system in case the integrated system fails. This though could be an expensive option.