I was running L2 for about 8 years (I just sold the game). I tried L5 for a little while, but I didn't like the missing Red Light animation, so I switched back to L2. The only time I experienced the endless multiball was after Secret Mania. I stopped playing Secret Mania a long time ago, so I haven't had the endless multiball in over 7 years. Sometimes my lock post would stay down for all three balls, but most of the time it would release them one at a time. It could have been mechanical, but it only did it every once in a while.