The guarantee is that you get at least 2 high quality blasts. I think the amount they thaw varies within the range you listed. I have had one transfer with them and got pregnant the very first time...I have since miscarried but we have done testing to determine that it wasn't related to the embryo. I used another clinic prior to RBA and have no regrets going with them, they have been great. There is a thread on another message board for RBA donor eggs and from what I have seen the majority of people have success on the first try and many of them do a single embryo transfer. They do have a guarantee that is $30,000 and you get 5 cycles and that one guarantees pregnancy but I don't think most of their patients need that many cycles, the nurses acted like not many people use that program. As far as the frosties go, I think they only keep them if they are high quality.