I'm looking at buying the H&S Ultra 2 in 1. I want to get the crown cap because of reviews I've been reading online about how much better it is than the original one. But with it being $34, I don't want to buy one for each size needle that comes with the Ultra 2 in 1. I'm going to be mainly using it for scale airplane models in 1/72 and 1/48 scale. Based on what size models I'll be working on, would the 0.2mm needle or 0.4mm needle be better?