Import Tarrifs from UK to US

Having ordered from Jon and had it shipped to Canada I've noticed that
the import duty is a huge part of the final cost, near 30%. What is the
import duty like to the states?

I want to take advantage of these great deals Jon's putting out but if
the duty doesn't outweight VAT, I'm just going to wait till I'm over
there in Feb and pick it up first hand.

Jaime