That is not true! The eXplorist line uses a patch antenna and it kicks butt in tree cover. Ask anyone who has cached with me. It routinely outperformed Garmin 60CS, Magellan Meridian and Sportraks on our last group outing (nearly 200 miles driven and 100 caches found). All those use the quadhelix antenna, said to be better under tree cover. I don't know what they did to make the patch antenna on the eXplorist line work so well under a variety of conditions, but they did a good job.
--Marky
I concure with Marky. My Explorist 600 kicks butt in terms of satellite tracking. Under heavy tree cover, and steep slopes on one side and lots of giant ferns I get around 4 sats. Up on the mountains I easily get 9 to 10 sats and accuracy down to 5 meters without WAAS. I'm in Australia. I love my new 600.