I love CS-Cart, I moved to X-Cart 2 moths ago but have recently decided to go back to CS-Cart after much reviewing of another scripts.
Interspire SC was my second choice, and there are still a couple of features that I would love to see in CS Cart.

1. (and I know this is a big mod) proper order management and partial shipping of orders/individual item shipping. This would then allow for proper back orders, part payment of orders, etc etc.

2. The order process in the admin is excellent. Select customer or new customer or anon customer first, then on same page add products using ajax seach on SKU or description. Very clean process, very fast (important when you have a customer on the phone).

3. Tracking numbers for all orders (haven’t found this yet in CS).

4. Allow customer to buy product? Checkbox. When unticked, an option becomes available to display price or message to customer (useful as sometimes there are products available offline only but still want them in the store).

If you want to make a business then must have a little bit of money for begin. My experience with the all free open source carts is not the best. Sure they cost nothing, but if you need a help…. Yes your help desk is the Google only. I have a few online business sites and my last (and must say the best) choice was CS Cart. The price is full acceptable and you get all features, the best support with 20 free points or 30 days(the Interspire is a nightmare) and 1 year free upgrades, all what a online store need. I buyed it from a reseller page webdesign-creative.com, they sell it for $217, the CS Cart price is $265, and they have often a special prices, you can get $20 off the price.

Yes guys, the TIME is money and if you want a free cart, then must spend 100+++ hours with setup, design, bugs, and, and, and….

I am very satisfied with my CS Cart and trust me, if you want to make a serious business and want many of customers and visitors, then you need a serious tools to do it.