Newbie diamond buyer, excited but needs advice choosing!

[dc20063]

With an upcoming wedding and a long "engagement" (8 years!), it's finally time to put a ring on this finger.
I like small diamonds but I want a diamond that will have fire, sparkle, & brilliance, and after reading through PS, I learned that cut is very important for this. Everyone is so knowledgeable! I've never purchased any diamonds before so I still have a lot to learn

Here are some I've found on JA, since I will be getting my setting from them as well. I want to make sure I pick the right one before I request an ASET image.

http://www.jamesallen.com/loose-diamonds/round-cut/0.43-carat-g-color-si1-clarity-excellent-cut-sku-423473

http://www.jamesallen.com/loose-diamonds/round-cut/0.43-carat-e-color-si1-clarity-excellent-cut-sku-432637

http://www.jamesallen.com/loose-diamonds/round-cut/0.43-carat-i-color-vvs1-clarity-excellent-cut-sku-369149

http://www.jamesallen.com/loose-diamonds/princess-cut/0.59-carat-j-color-vvs1-clarity-sku-218832

http://www.jamesallen.com/loose-diamonds/princess-cut/0.56-carat-j-color-vvs2-clarity-sku-243061

Thanks!