Type of Device for connecting to Mobile Broadband

[Levens]

When connecting to a Mobile Broadband connection through a cell phone provider, is there a difference between a USB device and a PC Card as far as quality goes?

The reason I ask is if the quality of the connection is likely to be similar regardless, I'll just use the USB device with my current desktop, rather than purchasing a laptop to utilize a PC Card.

Links to each of three types:

USB

PC Card

USB Modem - Not sure if this provides and quality benefits as far as overall connection over the other USB device.

Lastly, if anyone thinks there is a different device I should be considering for connection via Verizons Mobile Broadband, please let me know.

Thanks!