This is a very touchy and sensitive subject. I cannot speak to what Mr. Dituri has mentioned. If you are seeking training and buying a unit from him then you have your answer. I respect Mr. Dituri and have always heard excellent things about his training.
What I am about to talk about is my experience with the Prism rebreather.
I spent 3 days in Tennessee in early May at the new Steam Machines facility and spent almost all of that time with the PRISM unit. I spent the better part of my first hour with Peter Readey the Designer/Owner of Steam Machines in the lab. We went through the design aspects and the generational development of the machine. I found it to be a truly special machine and have been thrilled with the design and thoughtfulness of the unit. I have to say that the unit has been designed with the divers safety in mind (in my opinion.) The first day I spent going through the lab, meeting the staff, and trying to hold up my head at dinner after a solid couple of hours with the Peter. The second day was spent going over the unit and getting it ready to dive. We spent 2-1/2 hours during a pool dive and I after I exited I was walking on the clouds. One of the nice features is that you can shut down the on board electronics and we ran the unit manually. The sensors are ready directly by a handset and no batteries are required. At first switching off the unit is hair raising experience but after a few minutes life is good and you move on. When practiced so long and switched the unit back on; heard the solenoid click in and I knew the set point was holding. We went back to the facility after the dive did a tear down of the unit (post dive) and then broke for lunch. I felt amazing compared to a scuba dive for 2.5hrs.
The electronics are potted in a clear material that is helium proof. The system has Heads up Display- very nice, and the direct read information from the sensors in the handset. The unit was very nice and much lighter than my doubles.
For a unit specifics I would check out this article
http://www.rebreatherworld.com/articles.php?action=viewarticle&artid=13
If you are interested in the unit I would seriously recommend contacting Steam Machines directly. They have a number of people that you can chat with. A lot of their customers are the quiet type. They want the machine, the training and they go about there business. Steam Machines can go into specific with you.
Web site-
http://www.steammachines.com/
In closing I would like to say that the other two units mentioned seem to be fine units and I am sure other people have their reason for going that way. For me I choose the PRISM for the electronics, the mounting of the hoses-directly to the counterlung chest, weight integrated into the DSV, the radial flow scrubber and some personal research. In the end this market is buyer beware- that goes for all units and you have to be willing to accept the good with the bad. Do your research and understand what you are buying. I would suggest doing a few rebreather introductions. But those are my reasons.
Good luck with your decision.
Regards, Andrew