I've been checking
I'm also in the market for one. I've been looking around and find the Garmin GPSMAP 182 to be quite nice. It has a load of great features: plug-in chips, 10 gray-scale chart (color coming in January), great resolution, zoom-in zoom-out, etc. It retails for about $700 plus $150 per chip. The chips cover a wider area than the competition. Also check ebay. There's an outfit selling them new for a discount.