I have used quite a few of them, Woo, Magento, OSComm, Opencart, Zencart, ASP storefront, bigcommerce, Amazon webstore, veracart.
Amazon webstore is a nightmare.
I have never used shopify or presta.
For my needs Magento seems to win in each case as long as you optimize it so it doesn't take a long time to load. There is a huge user base, ton's of plugin's and it very versatile.
I agree with adamx12m and UnarmedGunman that once you get into woocommerce you think it is free, but unless you are willing to fark with the source code (and carefully consider each Woo update) you are going to be paying quite a bit to get all the features you need that would normally be free with an open source platform or semi open source such as Magento.
Curious to find those GPL licenses aesin mentioned. Shoot me a PM or share more please.
Bigcommerce, give me a farking break...closed source so you can't change shit if you need to customize something that they don't handle....and there is quite a bit of features that are lacking...they do make it easy for the non programmer 1 man show to get rolling though. Imagine this if you are on bigcommerce, you have a data feed with 20k products and it is the same 20k products that 200 of your competitors have. You can't create a script to automate rewriting of the title, meta, description etc. If you are thinking about SEO it is tough to compete if you have the same title, meta, product description, product name, etc. as 200 other online shops.Yes, you could do this locally first but if you have products that change every month or two it can get to be pain when doing bulk work.
Magento wins for me, after that I prefer Opencart, OScomm, and Woo, but paying for each little feature on Woo get's tiresomeand expensive.