Talk quality is great, and bandwidth usage isnt bad. the iPhone like phone buttons (like audio source and speakerphone) overlap or are insensitive. Overall the buttons are poor too respond. No transfer button? (Probably just as well Id never be able to hit it). And the phone auto answers at random (always awkward - I leave it on my desk.. Nothing touches it) and auto dials... Delay on push notification means you almost need to leave the app open. All and all, usable but needs improvement.