I hope itead works out.... beyond a certain size, OshPark's prices becomes expensive. OshPark is great though for tiny and small boards.
So I'm trying to use iTead for this medium sized prototype board.
Usually, I use an American company but at $100 for 5 boards (for any size... 1x1 up to 8x8 and bigger). However $100 for 5pcs of small and medium sized prototype boards is not a good bargain. For large prototype boards though, they're great.
On mass-production runs (100pcs, 250pcs and above), I use yet a different Chinese company (since '07). They charge tooling on the first run, but not on subsequent re-orders.
I'm spoiled by the other PCB companies with their instant online calculator, and web-based file uploads to update layers or maintain your gerbers. iTead's ordering workflow is not so good... and more suited for an online retail environment.