just wanted to put out a FYI, since i didnt find this info when i was searching....

I got a RFE for my pending spouse based AOS., they needed my medical again

USPS confirmed delivery on Feb 16th 2008
USCIS updated Case status as RFE response recieved on March 6th 2008

so we are looking at about 2.5 weeks., id give them some credit and make it 2 weeks, since Feb 18th was a holiday