My 2c worth, I won't buy 2nd hand electronics, I'd rather go new. I've seen on various forums that the GME stuff is not up to scratch. Rather go Cobra or Icom. When the brown stuff hits the spinning thing, you want to give yourself every chance of getting hold of help
the best is still a cell phone and a satalite phone has come right down in price to about 6k which is what im saving to get but you must have a 29meg for sea worthy but this is being fazed out for a VHF radio i hear.