regarding tres bien, i never got hit with customs fees because they marked things down, however they sent me a smaller size shoe and i returned it back the same day.
it took about 1 or 2 weeks to get refunded back, and they actually had the audacity to charge me for the return shipping (the shoe was sold out of every size). When I told them i didn't feel like i should pay for their mistake, their answer was simply, sorry, but we ask all our return holders to pay for the postage back, as it is the same as driving back to return product.
Fuck that. Flabbergasted and appalled me to the point that i will never ever shop with them again, no matter how good their deals are.
This seems to me like a prime reason to do a credit card chargeback. Was it just not worth the bother?