A simple, high quality ecommerce plugin?

I am trying to find a new plugin for my shop. Requirements: easy shipping module and not forcing images into set measurements (most of them stretch my image thumbnails). The only one I’ve found that does both of these without much effort (sorry to sound so lazy) is Ecwid, but you have to upgrade to add more than 10 products. So, is Ecwid worth it? Or is there another plugin that might work for me?

PS: At this point, I’ve tried Jigoshop, WP online store, marketplace lite, and cart66. I have also tried woocommerce and eShop (both of which I haven’t explored as much as the others).