Using the devices in wireless adapter mode (known as 'Station Mode' with the ZyXEL device) is a fairly straightforward process. Just insert the adapter into a free USB port on your Windows PC, run the included software to install the drivers, and configure the device via the management program. The management program (Figure 2) for each product operates in a similar manner, and allows for a good deal more control than the standard Windows wireless "zero config" utility. Note that regardless of the devices' similarities - even down to very similar MAC addresses - the management program from one device will not work for the other.
Figure 2: Management application main screens
Since the devices are wireless network finders at their cores, the management programs allow a good deal of information to be gathered about the wireless networks found by the devices, including BSSID, mode, channel, signal strength, and security options.
Both management programs used 'SiteSurvey' as the name for the wardriving option, and both of them found similar numbers and signal strengths of networks while in SiteSurvey mode. Profiles could also be created using both programs, including specifying preferences of networks to be connected to automatically.
The ZyXEL's management program had a few more features, including support for automatic DHCP renewal, and allowing the device to serve as a wireless AP. Access Point Mode (Figure 3) includes options for MAC address filtering and WEP encryption, though support for both WPA and WPA2 wireless security were sadly lacking.
Figure 3: ZyXEL's Access point mode interface
Connecting to the Internet through the AP worked well, once I properly configured XP's built-in Internet Connection Sharing feature. However, I found that the signal dropped sharply as I moved away from the device. Overall, Access Point Mode seems like a good way to set up a temporary wireless AP for Internet sharing, but lack of WPA support and the weak signal at moderate distances make it undesirable for more permanent usage.
Another plus for ZyXEL's finder is that it also ships with FUNK's Odyssey Client, which allows authentication with wireless networks using a number of different authentication protocols including 802.11X and EAP. Although FUNK Odyssey Client does not solve the lack of WPA support for Access Point Mode, it does allow the ZyXEL device to authenticate with Access Points using WPA and WPA2 while in Station Mode.
Another major difference between products is their driver support. While both devices support Windows (98SE, ME, 2000, XP, 2003 Server), ZyXEL ups the ante by including beta Mac OS X drivers (direct FTP download link) on its support site. These drivers allowed the AG-225H to outperform the built-in AirPort adapter in my Mac Powerbook in terms of wireless networks discovered, but they did not allow the machine to enter Access Point mode as of this writing.