I only know the top one and I feel I need to warn you. With fresh store builder you have the option to have everything done for you, like automatically. Amazon content, product description, features, prices .... Now some of that sounds logical and that is fine. BUT, and there is a big BUT, Google will see straight away that it is duplicated content and you will go down in ranking, and Amazon doesn't like it either. They can take you out of the Amazon Affiliate program all together.
Fresh Store Builder also uses automatic content spinning and you don't want to go down that road.

I didn't see your post until just now, I did post a post going along the same lines earlier. I am into building amazon niche sites, next to my what will be come my authority site but I want to do it properly, not half way. So I wouldn't mind knowing how some of our members are making their amazon sites.

I am not impressed with Amazon at this point in time. Looking elsewhere and will be making changes very soon. Thanks for sharing your information.

Shawn, it looks as though you're doing better than I am. I'm really disappointed with the Amazon affiliate business thus far. At 4% commission it's not a very good use of my time to promote their products. I have astores, text links, carousels, and nada! I've been looking for things to promote that pay a little better.

I just got started with the a-stores last week. Made my first sale yesterday. It was just the basic default theme through Amazon Affiliate.
I'm curious to hear about other themes and their success as well.
I haven't split tested yet.