Well, I didn't get an order into Sigg before they sold out of the styles I wanted. However, my sister read my post and offered to pick me up the same bottle that she had just bought herself, the Better Bottle by Camelbak. I went to the site to check it out and found that it is also BPA free.
So since I received it on July 4, I've been using it everyday and everything is fine. You can fill it up from water fountains nearly to the top and it truly does not leak. I can open up the valve and flip it over and...nothing, no spills. It does have an ingenious design in that you have to bite the valve in order to drink. With your bite, the slit in it opens up and the water siphons up. With this bottle you don't have to raise it above your chest to drink and never have to throw your head back, so perfectly safe for riding a bike or driving a vehicle of any kind.
However, keep yourself hydrated because if you wait until exhaustion your jaw might not have enough power to get the amount of water you want in one go. If you're wondering what the valve looks like after constant biting...mine's a month old and there is not a scratch on it.