We tried to return it due to poor call quality, particularly when in areas with 3 bars or less.
After installing iOS4 on my 3GS, the number of bars indeed did drop, but I was expecting that (Apple did warn us). And we all knew the bars were inflated previously as part of the iPhone 3G weak reception/dropped calls/make you feel better if you see more bars fix.
The iPhone 4 doesn't show radically fewer bars though, making it look superior to the 3GS in terms of reception now that both are running 4.0.1.
-------------------- Lisa Gade Editor in Chief, MobileTechReview