Pairing with your phone allows the Edge to display incoming texts or other notifications, and I also think it updates the weather display and probably a few other things that I don't make use of, so can't recall.
Sorry, I really thought (based on my use of the 130 for several years) that it would be ideal. The warning beep was always plenty loud for me. I don't recall a way to increase the volume (just looked, and there doesn't seem to be one).
Mine was mounted to my stem via the included rubber band mount. If you have an out-front mount, it might be harder to hear.
Link to anecdotal report on Garmin forum.