my own personal opinion and history of gps
started with old serial earthmate, only worked in the delorme programs == worthless
got the tiny delorme usb gpsr, was great, first one was stolen, bought another, worked for awhile and then loose connections killed it.
then I decided to go with a deluo serial gpsr, my favorite. because it's serial, it powers on as soon as my computer does and usually has a strong signal by the time windows boots (depending on location) the delorme usb one wouldn't start tracking until software was loaded.
I'm sticking with serial gpsrs as long as there's still a serial port to plug into.
I have 2 of those Earthmate USB. I have no complain with the GPS except earlier this year when Delorme didn't have a working driver for the GPS to work with Routis. They are all working perfect. No experience with any other receiver.