Had a test yesterday and he put you in a sound proof booth with headphones and a press button.
He fitted me up with a pair and told me to take a 10min walk out into Shrewsbury main high steet - Big mistake - I was out for an hour as the crumpet was so disgustingly underdress'd I couldn't take my eyes off it - No idea what sound was like.
Seriously it was a revelation -= so so much better than my old ones.
He then cleaned wax from my lugholes and showed me his list and one he had used - in the end I picked the top notch one with all the gismo's.
I am a babyboomer pensioner bringing in £10k a month
so it was back pocket change.
get them on Friday and a bit of research says they are Phonak or another Swiss maker. I will ask the question Friday - whether he will tell me is another matter.