I've had excellent results using KeySpan units, both the single-port, and four-port units, with both Windows and Linux. When I was using my rotators at Field Day, I used the 4-port unit with my Satellite Tracker Sr and FT-847. Now that I've gone to omnis, I just use a single-port "dongle" to control the '847. Never had a bit of trouble with them, and I've used them with other programs to control my scanners, and program my HT's. 73, Jim KQ6EA