Decided to try these ezsbc parts to replace a 323 regulator on a Bally SS solenoid driver board. Bought 3 of the new devices. Swapped one in, turned it on with nothing else,hooked up, just the power supply board. The +5V output was a little under 4V, turning the little pot only got it to about 4.4V. After about 5 minutes the component failed and put out the unregulated input voltage, around 14V. So I swapped in another, this time not using the huge heat sink, no chance of shorting anything and I made sure the pins were not touching the aluminum back box ground plane. Same thing, it failed after about 2 minutes this time.

I swapped my working original 323 back in and the machine is perfectly happy again. So, no idea why this happened.