I am right there w/ you...so just as curious as you are, and would love to hear how yours turns out. We are planning a FET transfer and have 3 frozen blastocysts. I keep feeling like I hear both ways...people on this forum that are successful w/ blastocycts def/transfers (which is very encouraging to hear) and then our clinic, which has a great success rate w/ their IVF/FET's has told me that we have about a 30% chance of them defrosting and making it...so I am curious to how it will all turn out. I am sure it does have to do w/ what SDScientist said, how the embryologist takes care of them!
GOOD LUCK to you!
I did an FET with one Day 6 blast. The cycle was unsuccessful, but the blast thawed beautifully. As long as it was frozen using vitrification then it should have a >90% chance of thawing okay. Also depends on how experienced your embryologist is with the freezing and unfreezing technique. Good luck.