i've ordered three sets of wheels in the last two years from overseas, two from the UK, one from singapore (souls). both UK orders were hit with a customs fee. nothing from the souls.

from reading other threads on the topic it seems super hit or miss.

also, i'm always ordering stuff from the UK (tires, random components, etc.) and the smaller boxes never seem to be hit with the customs fees, i think its the relatively large boxes wheels come in that arouse suspicion.