just a few thoughts to share since i just bought several pieces from FSH (a HAC40 and a Birkin 30 in Ostrich)
1. Birkin 30-35 is a hit or miss. You should plan to be there first thing in the morning when they open since they get only a few pieces every day and they are gone within hours. I arrived at 10:30 on a weekday and snatched one of the two Birkin 30 they have. I assume the other will be gone within an hour. This only means that you cannot be picky about what you want, ie. leather nor color. If you meet one sales who did not even check the computer for stock, walk around the store for awhile and come back to the leather department and try someone else again!
2. Hermes processes their own VAT which is a flat 10% refund. You cannot get cash refund and it is only refunded to your credit card after you stamp it at the custom when you leave EU. Thus, I do not think sending by post or any other courier is an option since you need the stamp at the custom on the form (unless Fedex can clear the VAT refund for you). And trust me, custom WILL ask to see the Birkin before they stamp it!
3. If you are not set on Birkin, they do have lots of Kelly 28 which is also popular with Asian ladies.
4. Avoid FSH on Saturdays... go at your own risk!
5. If all else fails, there is always the Birkin 30 in fuchsia croc with diamonds for a cool Euro 13,000. George V has another one in black.

At those prices, I assume they should still be there... but with Paris in June, you never know!
6. Tokyo is 5% VAT, and they deduct it straight away from the sales price on the spot if you show them your passport. (was just there in Jan 09 looking at Birkin also)
If you NEED or WANT it now, Tokyo is probably your best bet. Hermes in Ginza is in many ways just as impressive as FSH, not to mention the gazillon Hermes shops they have in Tokyo department stores. If you can wait, then a trip to Paris is nice, especially now the weather is so nice and it will be nice to go to the sale in June! #
Waitlist in Asia is a bit ridiculous since by the time it is your turn, you would pay the same price as in Tokyo from 2 years ago!