Question about PCB service (iTead/iMall).. if anyone has experience?

I don't think you finished filling in the form here
http://imall.iteadstudio.com/open-pcb/small-batches-pcb/im120418019.html
it shows 28.83 until you put in the correct sizes - 1.9cm is not accepted, it must be 5.1cm or more.Then the price goes up to $77.39 for 50 pieces.