So far I've only worked with Delorme Earthmate USB, Delorme LT-20, Garmin GPS 18 and a Garmin eTrex Venture. My observation is that the Delormes lock signal MUCH better than the Garmin. The Garmin GPS 18 will lose signal if tree cover even gets just a little thick. My rule of thumb is if there isn't...

I've had good luck with the Delorme serial emulator available from Delorme's site. Of course it may not work with anything but Delorme, I know my Garmin hockey puck antenna didn't play well with it. The serial emulator allows splitting up to 4 COM ports. That's my 2¢ worth. My next generation wardr...