From my experience import tax only applies to products that could be sold for profit and are shipped in bulk. So buying 2 esc's is fine but if you ordered say 20 then you would probably get taxed.

My flat mates ordered some servos from japan, one ordered 4 the other ordered 30. The order for 30 got taxed and the others didn't so there is another example.

I would go with the Botbitz ones. I use electronize but they are really twitchy and slow to respond on occasion so the sooner they die the better.