Is the era of wireless cards (rather than USB modems) coming to an end? The Kyocera KPC680 ExpressCard tries to strike a blow for compact, high-performance plug-in cards as the latest generation of USB-based cellular modems hit store shelves. It acquits itself well, but not quite well enough to be our Editors' Choice.

The KPC680 is a slim, elegant ExpressCard that also comes with a PC Card carrier, so you can slot it into older laptops. The end of the card is a flip-up antenna, and the white area near the edge lights up when the card has power or signal.

Like other Verizon Wireless cards, the KPC680 works with Verizon's VZAccess Manager software on Windows XP and Vista PCs; it supports Mac OS 10.4 and 10.5 as well. Also like all Verizon Wireless modems, it requires a $60-per-month unlimited data plan, and that plan isn't truly unlimited. (Verizon has been known to cut off people who are transferring what the carrier sees as too much data—for instance, with multi-day BitTorrent sessions.)

The card didn't do particularly well on our upload and download tests. We tested it against three Verizon Rev A USB modems over three days in Manhattan, Brooklyn, and New Jersey. It registered the slowest average and median download speeds of the four devices, achieving an average download speed of 639 Kbps and peaks of 1.46 Mbps. That made its average download speed only 83 percent that of the leader, the Sierra AirCard 595U. The KPC680 did beat the other cards 25 percent of the time—it's just that when it wasn't leading, it was often at or near the bottom of the pack. But it did the best of all four cards on uploads, with average upload speeds of 420 Kbps and peaks of 710 Kbps.

Part of the KPC680's problem may be signal strength, which was often a few decibels behind the leaders. USB modems jut farther out of your laptop, which may give them an edge in picking up a strong signal. On the other hand, that also makes USB modems a little more unwieldy in tight quarters.

Whether you should pick up the Kyocera KPC680 has more to do with form factor than anything else. If you plan to sock it into a laptop and leave it there, the ExpressCard form factor makes sense. USB modems are faster, but you have to plug and unplug them, and you could potentially lose them in the bottom of your bag. That said, we still prefer the Sierra AirCard 595U and the Novatel U727 for performance.

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