do you want to interface with your instruments?
You could try Pratical Sailor -- I believe they reviewed software programs not too long ago.If you currently have Raytheon/Raymaine/Sea-talk instruments, their autopilot, and especially if their HSB Radar, I would recommend looking at Raymarine Raytech Navigator.Although it is expensive, in addition to it being a high-class chart display/plotter, which can interface with most any GPS, it also can have bi-directional communications to your cockpit mounted RayMarine instruments and even control their auto-pilot.Its like having a complete 2nd station below at your chart table, which can show everything on the sea-talk 'buss' (with their 'interface box') and even download 3-day weather 'grib' files for free.I have been using verson 3 and now 4.1 for years (on my 30, only using Windows 98se, hence can't use their 5.0 version) with Maptech raster charts and don't know how I got along without it. It also works with C-Map vector charts.below is the link to Raymarine's software page...Hope this helps...