What do you think is the best shopping cart web software?

OsCommerce is good, they have so many benefits and many people have used it

I often used Cube Cart before it become paid. Simple and easy to customize.

Well, as for now, it's quite hard to know the exact answer on your question, otherwise there wouldn't be that many solutions present on the market There are different optimal solutions for different store owners. First of all, I'd advice you to list your specific requirements and describe the desired functionality. It would allow to make your search more specific. That's the best advice I could give.

I would like to go with OsCommerce.