I'd be worried that it would be way too harsh on their skin. I put some of that on myself once and it gave me a rash. I have sensitive skin, but then again, so do a lot of dogs. 
Thats about the only way to get the hair out of the ear. I would not use Nair, its made for humans and dogs ears are very sensitive. Its normal yo have them plucked once a month as it will always grow back.I am having a bit of trouble finding a good groomer here.
So far my dog has come back with cuts from too close shearing.
These people seem not to be able to handle a full size poodle.
Mostly I see they groom the very small dogs.
My standard poodle is quite large and very strong so maybe they can't hold him still enough.
I watched one groomer clearing excess hair from his ears and he seemed to just use resin for grip and yank the hair out.
If you could let me know the name of the powder, I will make a try at using it.
Thanks.
Leo
I am having a bit of trouble finding a good groomer here.
So far my dog has come back with cuts from too close shearing.
These people seem not to be able to handle a full size poodle.
Mostly I see they groom the very small dogs.
My standard poodle is quite large and very strong so maybe they can't hold him still enough.
I watched one groomer clearing excess hair from his ears and he seemed to just use resin for grip and yank the hair out.
If you could let me know the name of the powder, I will make a try at using it.
Thanks.
Leo