No Profile, No Service
Each BT device proffers its services through special Bluetooth profiles. For example, there exists a Dial-up-Networking profile (DUN), especially prevalent among mobile phones. Another common face is the Serial-Port profile, used to connect to printers, for example. If a device doesn't recognize a profile, users won't be able to use the services behind the profile. This can be a real problem if the File-Transfer profile is missing. Since this profile allows files to be copied between notebooks and PDAs, it ought to be very common. So it's all the more incomprehensible that some candidates don't recognize the profile. For example, users of the Com-One USB dongle and the Sphinx card have a nasty time copying files via the Serial-Port profile and the direct-connection software integrated in Windows 98/ME. This is an excessive detour.
User-friendliness is Key
The quality of a Bluetooth adapter isn't dependent on the hardware. None of the devices in the test had a problem establishing a Bluetooth connection. That said, not all the opposite terminals connected reliably, which is less a question of hardware than it is of the user-friendliness and the capabilities of the control software. That is what truly determines whether the adapter is effective in day-to-day use.
TDK took a step in the right direction by using the Widcomm software. No other USB dongles or PC cards offer such an intuitive interface as the TDK devices.
Test models - 5 Bluetooth PC Cards