Right. They are "Modem" drivers anyway. Used for Tethering or some Sync programs. Heck, maybe used for some of this adb and rooting stuff, I don't know.
The various incantations of Windows and Apple OSs shouldn't require a special USB driver installed to drag and drop files with the phone as if it were a flash disk.
My success has been, using the cable that comes with the phone and charger, having USB debugging ON, and using a USB1.1 port (like that replicated on a USB keyboard, or an LCD display with USB ports).
Windows will suggest that the device will operate faster on a USB2.0 port, but, it's a hit-or-miss proposition connecting with USB2.0 on my high-end laptop.
Interestingly, on my slower Compaq Presario V5000, the USB2.0 ports work. So I think it's possibly a firmware / speed issue in the negotiations during the USB device connection process.
But I mainly use the SwiFTP Server downloaded from the market and FileZilla client for the PC downloaded from the Web to connect to the phone and move content back and forth, and the USB cable for charging anyway.