just to clarify: i've been using my powerbook g4 with VPC and a garmin 276c via USB very happily for over a year.
Virtual PC 6.x, both Panther and Tiger.
BUT i believe it's because i have USB 1.1 on my powerbook. and i'm running windows 98 on the mac.
so, it CAN be done, but perhaps not if you have USB 2.x ports.
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