We sold many EAA firearms when I worked at a gun store including Bounty Hunters, mostly in .357, .44, and .45 Colt. The only problem we ever had with one was a broken main spring shortly after purchase. When the customer brought it back, I swapped in a mainspring from another gun while he watched. He was happy and had no further problems.
Ordering parts was, while not difficult, was not my preferred way of doing business. We would call the phone number and leave a message on an answering machine. There was no other contact with the company. In their defense, any requested parts always arrived in a few days and if we told them it was for warranty were free of charge. We only had problems with a couple of EAA guns, both easily repairable. The other was two screws rattling loose in an O/U shotgun.