Jan has made some very good points.
Generally different doctors specialize in different procedures. From what I have seen on the forum, there are very few doctors who really specialize in middle fossa (like the HEI doctors, Dr. Gantz etc). This is a very difficult surgery, I wouldn't let a surgeon who does not have a proven track record perform this procedure on me.
As for translab, vs, retro, many times it also depends on the neurosurgeon. My hearing was pretty much gone before surgery so it was not a consideration. 2 out of the 5 doctors I saw recommended translab. 2 recommended a combination of translab and retrosigmoid. The 5th does almost exclusively retrosigmoid and he is very good at it, with an excellent track record. I chose the 5th, not because I preferred retrosigmoid (like I said I had not hearing left), but because I trusted his expertise.
as Jan said, there is no guarantee, the best thing that we can do is to research the credentials of the surgical team, make sure we know what their outcomes are (and I am not talking just "stats', but real patient outcomes) and then hope for the best.
Marianna