ordered a stock 45, and the fit is actually much better than the stock 46 toj0 i used to have. it's actually really surprising to me how big of a difference a half size can make, since my toj0 had a lot of room in the sleeves especially. whereas i could easily fit a sweater and more underneath the toj0 and be able to move freely, i was already experiencing tension in the leather as i bent my elbows with nothing but an ocbd underneath with the v1. buttoned up, too, i could feel it getting a bit restrictive, but this is actually all good since i was looking for a slim fit (which the 46 toj0 failed to provide for me) to begin with. i will say, though, that the back of the jacket kind of flares out a little since it seems like it's horizontally longer than the length of its ribbing, but i'm sure that this is something that will settle down with time as the ribbing stretches.
i hate bathroom selfies and would otherwise never take them, but i took two just to give you guys somewhat of an (crude) idea of the fit (for reference, i'm 5'8, ~125 lbs