Hello,
Been a while! Anyway, I'd like your opinions on whether the size of the oil feed hole on the supply line for the turbo can slow spool. I bought a replacement turbo for my car (not a VW), that didn't come with and oil supply banjo. It is an M12 bolt, stock is M10. But I couldn't find a banjo with a small-ish hole. So I used the banjo attached. I've always had very terrible spool. So I've troubleshot everything, and now I'm thinking maybe too much oil volume going to the turbo can somewhat slow spool?  I'm I clutching at straws, or is it a possibility?

Ball bearing is more prone to oil, wet/journal bearings can handle more oil but slower spool can be related to more than sufficient oil supply.