We use Easy Callbox. The website is
www.easycallbox.comIt was designed by a physician, integrates with AC, and works smoothly.
The cost of these products is always an important consideration. This one costs $1895 as a one time fee. That may sound like a lot, but the other systems typically have a cost-per-call. This way, we own the hardware and software, it takes a minute or so a day to set up the days calls, and we never have to pay anything more. You can do your own math to decide how many "visits that otherwise would have been missed" it takes to pay for the product.
Be aware, a practicing physician runs the business, so the website looks a bit low-tech and support is not always speedy, but the product works very well for us.