Be careful before you buy the latest ICOM A6 or A24. They supply a headset adapter with the transceiver. However with many headsets (I have tried DC and Bose) all you get is feedback when you try and transmit.
This is a known problem by ICOM (according to one of their dealers) but they do not reply to any communication about it. I am therefore stuck with an A6 which cannot be used as a backup. I believe many others have found the same thing.
The models before the A6/A24 sometimes come up on ebay and seem to work well.
So check carefully before you buy if you do decide on ICOM as they are useless as a backup in case of radio failure.