I definitely get the convenience factor.
That's just it, my lady loves it. Several of my coworkers love it! (We have them in a few company cars) Unfortunately I've had more negatives that positives when using it. Like you, I've had similar experiences. I've had intermittent connectivity, phone overheating, poor battery life.
I'm definitely not against them. In my limited experience, it just didn't work well for me when I tried. There's simply to much to keep up with technology. What's current today might be obsolete tomorrow. There's more than a few different ways to skin a cat as long as it can connect and work, that's all that matters. Ron has good taste! The unit that he linked has a shit ton of positive reviews. Might just be the one.