sbright33:
I've got the higher powered ones series 1. Nearly a mile outside, half mile thru trees, with tiny rubber antenna. Measuring packet retries after changing the max retry parameter to a higher number is a better indicator than RSSI. Even when 100% get thru, you can measure the % retries before they are successful. It was difficult for me to figure out, but now it is easy to put them to sleep even for a short period of time to save power using a hardware pin between packets.
What do you have your packet retries set at?