I first went to Costco almost three years ago, when only my right ear had been affected with Meniere's and was, therefore, downright useless. I went because my "good" left ear had age-related deafness, so initially my loss in that ear was moderate. However, a year ago, Meniere's went bilateral, meaning that suddenly I heard nothing useful from either ear most of the time. I've been back to Costco several times, due to the difficulty presented by fluctuation in hearing loss (one of the really swell features of Meniere's). Every time, there's been a big improvement in my hearing as a result. The patience of the woman at Costco as my hearing has changed has been impressive. She's the only one of all the medical people I see who knows anything about the disease, which really surprised me, as I had initially gone to Costco simply to save money (at the time, my hearing simply needed a boost). She understands the two other "features" of this damned disease: distortion and recruitment, and has made appropriate adjustments. I hadn't been able to listen to music for well over 30 years (since Meniere's had affected my right ear) due to the distortion. She adjusted my aid so that, WOW, I can actually listen to music once again. She is NOT an audiologist, but she has done a lot of self learning to possess the depth of knowledge that she has.