I consulted with Dr Critz when considering treatment options. One of the rad-oncs in the group performed my wife's breast cancer radiation therapy. They are highly regarded and I know several men who used them. Eventually I chose HDR brachytherapy rather than permanent seeds, so I did not use them.
When I was studying them, Dr Critz provided me with an older study that tracked men over 10 years and it was segmented by risk at diagnosis. It was the first study he reported that showed the Brachytherapy/EBRT combination being as effective, and, in intermediate and high risk dx, more effective than surgery for long term cancer control. Critz claims to be the first to use adjuvant EBRT with Brachytherapy and calls it Prostrcision (website is www.prostrcision.com). He also published 15 year results a few years ago, but I don't remember whether it separated patients based on risk level at dx.
A little over two years ago Northside Hospital purchased them and greatly increased the marketing and advertising. The adds are tastefull and refer to the website www.curingprostatecancer.com. They also conduct weekly dinner meetings and free PSA screenings at their main treatment facility on the east side of Atlanta.