I'm considering taking the plunge into the world of CIEM's with the Heir Audio 4.A firmly in my sights (at least for now). Winnipeg Hearing Centres (www.winnipeghearing.com) are listed among partners for Etymotic and ACS and a recent chat with them suggests they know what they're doing. They sell other custom products including audio so have experience in this regard. That said, interested in hearing of any first hand experience or alternatives from others in the area. Absolutely want to avoid any fit issues with the 4.A's.