If it fired with the safety engaged, something was definitely defective.
I've had 4-5 of the Firestar Plus models over the years. I liked them all, but always had other guns that I liked better. Two were Starvel finished. I got them at good prices and used them as "trade" fodder. Did the same with a couple of DaeWoos, an even better gun that is not appreciated by most shooters.
The triggers on the Star guns can be improved by a gunsmith with almost no effort, and the magazine safety can be easily deactivated -- if that's your choice.
Mine were always reliable and accurate. If I found one for a good price, now, I'd grab it. Never had any kind of parts issues. The best buy was one I picked up a few years ago at a Pawn Shop -- ANIB -- for $175. (They obviously didn't know what they were selling.)