The best ecommerce solution out there is the one made by or used by the person you are asking. Everyone has his or her favorite. Each CMS you mentioned has a big learning curve, and I'm not sure I'd touch any of them without some programming know-how (but I'm a scaredy-cat).
Just so you are aware, there are lots of hosted carts out there that take the stress out of ecommerce, and I think are worth considering. Things like Shopify, Goodsie, Big Cartel, 2Checkout and many others. You don't have to worry about any of the security issues that you'll face if you host your own software. You just pay a monthly fee of some sort.
I suggest you look int those and see if they would suffice before assuming you have to take on those giants you listed.
I've played with prestashop and I thought it was nice. open cart is another good looking one. I think what you use depends on what you have. If you are paying for web hosting it is a complete waste of your money to purchase a hosted cart services no matter what anyone says. Frankly, imo, even if you didn't have web hosting yet it would be a waste of your money since all it would take is some extra effort on your part to host your own ecommerce solution. If you are just starting your online business shared hosting is fine. It will take some time before you get enough traffic to outgrow shared resources in most cases. Hopefully your host has options available and can upgrade to a vps or dedicated server if the need arises. Most of these hosted carts charge 25+ per month and there is no reason why you cannot simply get a vps for that much if you want more freedom than what basic shared hosting packages offer. Also if you are first starting out I would use something like paypal as a payment processor until your store is well-established since it does not cost you anything out of pocket to use them.
I noticed you mentioned the words "Buggy" and "I don't have any programming skills".
These 2 points alone should be enough reason to stay clear of open source solutions like Magento and osCommerce.
Try a commercial solution like BigCommerce.com - they have plans starting from $24.95 a month and this includes your web hosting and support.
It comes with over 90 pre-installed templates to use too, but there is a directory on their site of web designers who can custom make a template for you.
I have to agree fully with this statement. BC is a pretty straightforward solution when it comes to client usability.
One thing you have to look at when you're going hosted vs. standalone is the support. With BigCommerce, you get updates, live help, and pretty much any question you have is answered with a video.
Don't get me wrong, Magento, OSCommerce, and any other cart you can think of are great options, but if you're looking for an all inclusive solution, the hosted options like BigCommerce are going to be your ticket.
Magento is the best eCommerce platform because you can choose wide variety of free Magento templates for your website.
You get quite a few with any e-Commerce solution nowdays. Magento is great but it has a deep learning curve and it may be quite expensive. It is not a tool for every business.
Templates and how easy to build a template should be one of the things to take into consideration but not the only reason as your comment suggest
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