Panhndl,
I live about 20 miles from the US warehouse (I am just south of Seattle and the warehouse is in Lakewood......... 20 miles by freeway) and my last order for 4 batterys took 4 business days to arrive by USPS Priority Mail.
Your situation is different in that your order is still processing. The order still goes through the Hong Kong processing and then is relayed to the Us warehouse. I had an experience dealing with another large chinese warehouse/shipping business and my order was delayed for almost 2 weeks until I opened up my junk email folder and saw that there was an issue with the CC I had used. It was not verified with them so they kept my order in processing until We worked out the fact that the CC I used was legitimate.
I would highly suggest that you get on the HobbyKing website and find thier US customer support number ( here it is: USA Toll-Free 1-800-607-5803 ) and have your order number ready. If there is an issue they should be able to identify what the issue is and let you know if your products are backordered (which means entire order does not ship until all products ordered are available) or if there is another issue which they cannot resolve without some input from you.
I rea;ize you may have already taken these steps but 21 days processing sounds like there is an issue that they cannot resolve until you contact them. Let us know if you find out anything and maybe we can save the next guy from waiting blindly for 3 weeks. Good Luck!