But a doctor is allowed to tell you which brand s/he most often implants.
There is no better or worse technology among the 4 mayor brands in Europe. Take a dice and mark “1” as Cochlear, “2” as AB, “3” as Medel and “4” as Neurelec/Oticon and roll the dice. If it shows “5” or “6” than roll it again. If you are unsure then roll it again, too 
I have chosen my brand by the time I need to travel to the hospital for each adjustment. And there are a couple of them.