I suspect the range you quote (700 Ft) is the indoor range number (this assumes AP to clients) whereas the clients have a low or zero gain antenna and there are cubicals, office walls and other obstructions present.
The AP1231G is very similar to the BR-350 with the exception of two things. The BR-350 is 802.11b only and therefore it's transmitter is slightly better with respect to out of band emissions since it is only operating at 802.11b speeds and does not produce OFDM emissions. Therefore, you can run higher gain antennas with the BR-350 (up to 23 dBi is what we have FCC approval on). however; when using the AP1231G you should keep your antenna gain to 10 dBi or less as the faster speeds of the AP1231G (using 802.11g) restrict the gain to 10 dBi.
If your WISP antenna exceeds 10 dBi I'd just use the BR350 it's a fine product and it's unlikely you'll be able to exceed 25 miles anyway at rates greater then 11 Mbps.
Another option (if using the higher gain antenna is a requirement) would be to use the BR1300, this Bridge is designed to run OFDM emissions using the higher gain antennas with less out of band emissions so it's the perfect choice when using longer OFDM (802.11g) links.
