I had a cheapo Samsung flip phone on T-Mobile that would always drop calls about six blocks from my Royal Oak home. I was looking at the coverage/signal strength maps at the T-Mo site the other day while researching whether to use AT&T's or T-Mo's network with Straight Talk (if only you could get more than 100 minutes on the $30 T-Mo plan, like 300 or so) and there was all sorts of weak spots in the areas I'm most around. Going to try AT&T first.