I've been using a Lorance Global Map and it's been good, although I can't say the same for they power cords

. I got it on Ebay and saved about $150, including the mapping software and computer interface cable. It's very easy to use, the only drawback is the small screen, but if your looking at a portable, I think your going to find they all are lacking for screen size. I'd recommend that unit, but when I researched buying, Garmin seemed to be a highly recommended unit as well.