An observation: when it comes to audio connectors, people who need their connectors to work when they are running back and forth on a stage under hot lights and yanking their equipment around by the wiring — these are the people most likely to have evolved sturdy connectors.
The photo at right shows three quarter-inch stereo plugs. The first, I bought in bulk via mouser. They are pretty cheap: thin metal tables, tight spacing in side the connector, and the strain relief is molded plastic that is part of the barrel itself. The middle ground is from Radio Shack, probably a few years back. The barrel is phenolic plastic and there is no strain relief.
At bottom, a much sturdier metal shell that screws together and compresses the connections. This connector is from Guitar Center, and has some heft. I think it was a couple dollars more than the Radio Shack connector, but there is no question in my mind that it will last decades longer. While I was at Guitar Center, I also bought a few shorter mono-cables as patch cords and about thirty feet of two and three-conductor shielded audio cable.