The SR2 didn´t work with interferences.... not a good card for me....
I prefer R52 or Senao NL2511 (802.11B 200MW)
how could you compare a 65mw card with a 400mw card ?
the R52 and cm9 are the same 65mw ,,
SR2 for broadcasting with 12 omin will give you a good -db in the client side , and if you used a better high gain directional antennas in the clients with small beam the -db level will be better ,
finally if you want a good recieve level but with higher much price for each client to increase the distance you may use the LS2 , which has also SR2 card built in an 180 MIPS mhz processor , but it just work as a client bridge , your sensitivity may be increased with 6db or more for each client