We have tried both calculators and all are accurate in the cups sizes and almost accurate on the band size. The "Thin and Curvy" way to measure puts us in a smaller band size but the cup size was correct, but we used that as our starting point. The "thin and curvy" way to measure is accurate with the lingerie brand Panache. Always start with the smallest band size and if it is painfully tight than go up a cup size first, if the cup looks big and the band is still painfully tight, than feel free to go up a band size and down a cup size. Sometimes when the bra band feels painfully tight it means the cups might still be too small, so go up a cup size first to double check. If the band is riding up in the back and you have to wear it in the tightest hook than go down a band size and go up a cup size. When you have a new bra the band should be snug on the loosest hook so the bra will last since bras stretch out when you start wearing them. Bra Size calculators are just a starting point so you know what sizes in bras you will try on and than pick the size that is comfortable snug in the back and make sure the cups cover all the breast tissue. Remember not all D cups are the same exact size. The cup size gets larger as the band sizes also gets larger. For example bra sizes 28dd,30d,32c,34b,36a are all the same cup size, the difference is the length of the band.
We also liked: http://www.barenecessities.com/calvin-klein-seductive-comfort-customized-lift-push-up-bra-f2892_product.htm?pf_id=CalvinKleinF2892&search=&manual_cm_sp=SlotLocation-_-R7C3-_-CalvinKleinF2892
Other cool blogs about bra fitting that have very good information on bra sizes are:
fullerfigurefullerbust.com and sophiajenner.wordpress.com
-Krystal and Elisa