I’ve talked to several well known restorers about Banzai Run. It and several games of that era are known for having some quality issues. They claim it (paraphrasing) won’t tolerate the process due to an issue around the insterts.
I’ve been on the BR waiting list since 2013. No production seems to be in sight. I can only assume it’s a small list of buyers and they need a certain number to make it profitable.
My old BR is rough, but plays fantastic. So no worries here. Reminds me of an old, trusted dirt bike! Here’s my son helping me clean it up.