My K-20 is so equipped.
It was delivered with a standard sporting stock.
The previous owner sent it to Ottsville along with about $500 to have a 'factory' adjustable comb installed.
He fiddled with it for a few years.
After he went to the big gun club in the sky, I bought it from his estate.
I've never changed the setting he had, and when you lay the gun on top of one with a standard stock the comb height and angle are identical.
I find that mildly comical.
It does make me look like an expert though, right?