This is in response to lacough about signal issue:
Yes I am having the exact same issue. I have the app SignalCheck Pro installed and have had for awhile. It appears from monitoring that app over time that on 4.1.2 the signal strength algorithm for displaying bars was based on the voice (1X) signal. After the 4.3 update it appears to now be basing it on the signal strength of the data connection. So if I'm on 4G and have a weak data signal my phone will show 1 bar even though my voice coverage decibel strength is sub -80. If I'm on 3G it will base it on the EV-DO signal strength and only when I'm on 1X does it base the bars on voice coverage.