I've just read their, rather information free, web site and, as far as I can tell, they're using multiple repeaters to provide service within a city environment.
I don't know if anyone reading this thread has done any line of sight work, but setting up such a system in a city is really fraught with problems. Reflections and refractions can cause deep fades and if the objects causing them are moving, cars, busses, trucks, trains etc, there is no way of predicting the time or depth of the fade.
Proffessional line of sight installations on fade prone paths use space division and/or frequency duplexing to ensure that two signals with different fade characteristics are received. This is why you frequently see two dishes on a tower both pointing in the same direction. A single, simple dish cannot provide this duplexing and is subject to fades.
Didn't Telligent try this a few years ago and sink almost without trace? They wound up providing only 20% of their links via radio and the rest via leasedlines, which they couldn't afford.
Greg's system sounds like a good, solid line of sight system and, if there is no source of reflections or refractions in his path, then the system should be solid.
Trying the same thing in a city environment is really fraught with problems.
Actually, Greg, I'd be interested in finding out where you got your kit and connection, since I'm planning to build a house in northern Vermont, miles from anywhere. the lack of a good, fast internet connection has been bothering me.
Regards
John