I've had Costco hearing aids for a year now.
I assumed I could better if I paid 3-4X $.
In my case I think I was wrong.
I bought the fancy($$$) ones.
The Costco type did everything the fancy ones did and hooked to Bluetooth easier and sounded better.
I am going back to the $$ expensive place soon for a tuneup.
If I don't get improvement I can get a full refund.
By the way, I don't recall anyone saying the Costco ones have a 90 day full refund policy.
Most audiologist have a similar guarantee.