This should probably be in the 3rd party section, just so's you know.
For your average TFSource customer, yeah...their shipping's expensive. PSX are based in Hong Kong IIRC (or if not, then pretty close by), so shipping to the US is pretty hefty. Especially when compared to the "free shipping over a certain amount" deal many US sites offer.
Poor Americans, I'm crying on the inside, really I am.
For us in the Asia-Pacific region, it's quite a bit better. Still not cheap, but not terrible either. I got 4 of the Feral Rex set from them and 2 from TFSource 'cos PSX was out of stock at the time, and it worked out about equal per figure either way - and that's not counting Felisaber/not-Catilla who they accidentally shipped ahead of the rest, and were good enough not to charge for the shipping. They even apologised for it...no worries, guys!
Also, to PSX's credit, they were fantastic on the customer service/reliability side of things.
That said, TFSource also got the goods sent just fine in the end (though their customer service wasn't nearly as good as PSX), and depending upon what you're looking for and the availability thereof it may well be easier/cheaper to try through a larger/more established store as part of a larger group order.