For those who like SOC but would like something possibly a bit further along in capabilities, there is x-cart, which is a paid for derivative of OSC. I've had just one experience with it, when one of the forum members who hosts with me asked for me to install it for him. For under $ 200 it did seem like it might be a good way to get some popular additional features.
There is also CRE Loaded, which is a version of OSC with about 50 of the most popular mods already installed. It used to be free, but they have lately taken the CC approach, with a fee to remove their copyright info.
And ther eis also OSC Max, which has the advantage of having a built-in import / export capability, which OSC and Zen do not.
You can actually go on and on about these for days. The fact is there are few really true "out of the box" solutions in the free open source field. In my own case, I am limited by my long ago choice of a gateway/card processor. I first have to see if Transact is supported (seldom) and then if there is a current version mod that will allow me to use it. Or, as a few do offer, there is an easy to set up wizard type program to allow me to enter the necessary info to enable iTransact on my own.
In the end, it's sort of like trying to tie down exactly SEO with Google. As soon as you think you've got everything covered, something changes. In some case, no matter how much you compare features and benefits to your specific needs, something will change. Often, it's your needs, but there are times when the carts will change and discontinue a feature that you need that is not really popular with others. (Note in the new CC version comparison with the current version some feature lists are shorter than the current one - for instance payment processors.)
There is no one right choice for everyone. You either have to adapt to the closest match to your needs, or pay for some mods and end up with a custom cart.
One thing I do think is way over-blown is the look of the cart. I honestly doubt that anyone has ever left a site that had products that interested them because it looked like a "CubeCart Site" or an "OSC Site", etc. Customers and prospects come because of what you have to offer. As long as you present your goods in a reasonable manner, they are not going to leave because they visited another site with a similar look.