I have experienced the following problems with 20931:
- The TouchFLO 2D Dialer (Version 1.0) doesn't always answer (or start a call) when I press any of the available "End/Call" keys.
- Bluetooth HFL is very unreliable (randomly drops pairing) - which may be related to the TouchFLO 2D Dialer, but I'm not sure.
I have moved back to 20755, which seems better. However, it still had problems with the TouchFLO 2D Dialer.
I am now using the HTC Diamond Dialer, which is more stable.