I go full up on 450 as well. V3 i go .5 up and same with knit rnr (both fit very snug tho, especially v3 almost too snug but i dont mind). Havent worn 350s in years but I did go up full size on those as well when i did.
The boots .5 up give me the slightest bit of heel slip but it isnt bad, i...