Yes, that’s part of the issue. If you are willing to wear occlusive molds as I am, you can wear M&RIE receivers and defeat feedback even with a steep ski slope loss. But if you cannot adapt to the occluded sound of your voice, you won’t be happy with the result. I have no problem switching between not wearing HAs and wearing an occlusive fit. I have a steeper ski slope loss than ReSound recommends for M&RIE receivers, but I greatly like them. Besides ReSound’s conservative recommendations, maybe some HCPs don’t like all the fiddling and the possibility of returns and try to discourage users from departing from the well-beaten path of standard receivers. My audi said she would swap out M&RIE receivers for standard receivers at no charge if I didn’t like the M&RIE receivers, but I would have been out the cost of ReSound custom molds with Select-A-Vent that I had made for the M&RIE receivers. Standard receivers won’t fit the same molds, AFAIK.
There’s a thread with info on ReSound M&RIE receivers, referenced by the following post: ReSound Omnia M&RIE - #4 by jim_lewis