2007 A4

So I got the no reverse PRNDS blinking and check engine light. Did some research and had an idea it was the TCM. Took it to audi and they confirmed thats what it was. Their cost is outrageous . In reading from forums i see that there is a company that will repair the module. Can anyone advise on their experience with this if they have had it repaired and is it succesful.
I know dealers will have their recommendations but they are telling me that these so called repairs to the TCM are not that succesful more than half the time.