Personnally, I dont like the combined instruments. Choice of radar will really be dependent on your own method of operation
I am happy with a lower power set, so that I dont feel that I always have to have the engine
running to use it (2kw) this means that the accuracy and power to work
in really wet weather
is not as good as some of the more expensive options. On the otherhand, the scanner is much lighter, so can go up the mast
, and thus give me greater range.
The next decision is what extra bells and whistles you want with the radar. If happy with a head
up, then that is cheaper, as a proper north up display requires a decent gyro (and thus more power). Another gizmo that is finding a lot of pundits is the Marpa/arpa system which will help you work
out what the other boats are doing. Again an expensive option, and I personnally dont like it cause it clutters up the small screen and can overlay other contacts. There is a new system that will be available in a couple of years (AVIS) that operates from a signal pushed out by the merchant ships and gives their position course and speed which should be simpler tha marpa and cheaper, and more accurate.
IMHO a couple of 6-7" displays with radar on one (preferably North up) and plotter on the other, both visible from the helm
, provides a good set of instruments.
On the otherhand, I have seen a boat with 2x15" displays that were able to be used for anything, and on a long journey, the helm has been known to watch a dvd