I once took my ACDC Pro to a one day tournament. It ran non stop for a 8 hour period with the flippers and every other part on the machine copping an extra flogging.
I quickly cleaned the balls and gave the playfield a clean each hour. Nothing ever got hot and nothing ever played up.
The existing hardware works perfectly. Any improvements over this are a bonus. Prob got a whole years worth of my home playing in only one day. They are built well. Even in current form. Just some feedback.
Just don't hold the flippers too long then, you'll see!
Yep, the missus popped a transistor on my Tron holding the flipper for to long while she joined a mate an I in a conversation. She may have been a little intoxicated at the time, so I cut her some slack...... 
Definitely don't hold the flipper for extended periods of time.
stern's are definitely not made for women. Still haven't met one who doesn't take 10 minutes to say something that would take a guy about four words.
I'm guessing you would never see a current stern having coding like on a tz where you can put it in 'pause mode' with the flipper up.
