Welcome to the board!! You can find write ups on all of the mainstream rebreathers in the rebreather section.
As you will see, everyone has their own reason's for wanting a certain unit. As a dive shop owner wanting to sell and support rebreathers, you will need a general understanding of all the units.
The best way to get started is to get involved, get educated, buy one and get trained. You will then be able to start formulating your own opinions.
The first rebreather that you are attracted to might not end up being the one you would ultimately want. You don't know what you don't no at this point.
Have fun!!!!!!
and Welcome