Bought My AMG ....didn't take it back to Mercedes for Tweaking ..
Your Mercedes dealer did the tweaking. Car dealers go through them and make adjustments and corrections so you don't get out on the road and kill yourself.
Stern is tops in quality control. And the games then go to CGC for more of the same.
Then they get put in a truck and bounced around the country to you. Things can happen beyond anyone's control.
And from what I've seen in tech support so far. With 100+ games out there, the problems have been few and far between.
PPS/CGC/ with Stern assembling, are doing a good job to deliver you the best pin they can.
LTG : )