Wow! Misinformation abounds!
Re: t-coils. Some Costco hearing aids have them, some do not. And in the ones that do, sometimes the dispenser will activate it, sometimes not. T-coils are not always simple to use with the telephone. Further, buildings with loop systems (designed to be used with hearing aid t-coils) are somewhat rare in the U.S.
Re: repairs of aids. Most hearing aids sold in the US these days are receiver-in-the-ear style (also called receiver-in-the-canal, or RIC). They have many advantages, but the disadvantage is that the receiver wire (which runs from the body of the piece behind your ear, down into your canal) is susceptible to breakage. Depending on the dexterity of the hearing aid user and the care exercised during putting the instrument on and taking it off, damage to the wire can occur on a regular basis. Usually this can be repaired in the hearing aid center. Excessive wax in a user's ears as well as heavy sweating will also affect repair frequency.
In short: frequent hearing aid repairs are usually in large part user issues, not a 'lemon' or 'bad' hearing aid.
Re: Rexton, a subsidiary of Siemens (look it up!). If you compare the specs on top of the line instruments from Siemens vs Rexton, they're pretty much the same thing. There is nothing 'stripped down' about them. Why does Costco sell Rexton instead instead of Siemens? Could it be other hearing aid providers have a fit every time Costco gets a big name contract, making it difficult to compete?
Rexton is just another name for Siemens, my friends. By the way, Siemens spun off the entire hearing aid division a couple years ago and it's now called Sivantos. The owners are a Swedish company and a German family, no longer Siemens.
Costco doesn't sell junk anywhere in their warehouses. If it comes to a buyer's attention that a product is sub-par, they'll pull the line. Costco is not in the business of fooling or cheating their members. They take the hearing aid business very seriously and work hard to provide a quality product.
However, your happiness with the product will be affected by the expertise and experience level of the individual who is fitting you, as well as his/her attitude. If you get a surly or burned out or lazy or very inexperienced dispenser, it's not going to be a good experience, even if the hearing aids are great and well-priced. As Costco tries to keep up with the demand, some personnel may not be as fabulous as others.
If you don't click with the dispenser in your chosen Costco, try, try again. There are some great people working in their hearing aid centers; try another one nearby!