Wi-Power is internet service provided by TransWorld Network, Corp. We started with a PMP 100 omni AP in Moriarty, NM and as the demand increased we added two PMP 450 sectorized APs. I'm blown away what the PMP 450 equipment delivers.
2.4 GHz could work in many situations, but we will have a PMP 450i 900 MHz variant launched in the 4th quarter this year. For tough links and many NLOS situations this may be a better fit for your network, if you can wait a bit.
We also upgraded from PMP 100 to PMP 450 5.7Ghz 5mb to 10mb. we have 3 AP with 90 degree att. on the tower plus 22 remote SCADA sites with reflector dish. The 450 are rock soild plus we could use our old mounting stands and reflector dishes.