I think osCommerce is a great option for all the features it has. It has a strong community and hundreds of plugins and does all sorts of cool stuff you'd want it to.
I would not recommend it, however, if you want to do something with the visual layout other than the standard "block-oriented" style. I had *major* - yea, nigh unto alcoholism-inducing - headaches getting it to look like the mockups the customer gave me because they didn't follow the normal 3-column, boxes down each side, banner on top layout (there is some flexibility there but not nearly as much as I needed). Internally, there's a ton of intermingling of display code with business/database logic. If that doesn't bother you then I think it's a very good option.
A couple of other things I noticed about osCommerce, though probably not a big deal: when I used it (about 4-6 months ago) the affiliates plugin had a ways to go before you could call it usable (I had to read the code to understand anything about how it worked), although I'm not really complaining because it's some dude doing it in his spare time. I also really wish it would let you customize what fields each product could have.
If you want something with a better split between domain logic and display logic, ZenCart looks like a good way to go. It's an osCommerce spinoff by people who seem to have had the same complaint as I did. They didn't take it as far as I wish they would have - I'd really like an ecommerce app that simply handed the templates a bunch of data structures and let me display them however the heck I wanted to - but it's a large step up from osCommerce in that respect.
The other one I can mention is Interchange, which does so much you begin to wonder if there shouldn't be college degrees available in it. But my minimal experience with it leads me to believe it's, well, unwieldy.
Brett .===================================.
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