I love Vitacost. If you order $49 worth, then shipping is free. They also ship fast. I usually have the order within a couple of days. As Aaron notes, they also have coupons and specials when you get on their email list. They just sent me a 20% off When they have other promotions, they allow you to stack the savings. So, if they are having a 20% off of food and drinks and 15% off of Bob's Red Mill, they let you have both discounts.
My only issue is that I've had a couple of boxes where an item broke open. The last time, it was a bag of milk powder. However, I notified them online, and they quickly sent a replacement. I've even order almond butter and maple syrup from them, and the glass jars were well wrapped and arrived undamaged.
So, by all means order from them. They are one of the best deals out there.