Another cart you might want to look at is Modular Merchant.

I have used http://www.zeuscart.com which is the best open source e-commerce shopping cart software. Beside all other features this software is based on PHP Smarty templates, this makes it very flexible, seo friendly and easy to modify. They provide good support also.

hi! i've been using cre loaded but now i'm thinking about trying something different - maybe pinnacle cart. It seems to be not bad.

Though i don't exactly know how this should be done maybe by any chance somebody knows how to upgrade to pinnacle. I would really not want to lose any of my data.

Thanks!

found this service on the net - cart2cart It seems to automate switching from one shopping cart to another one. Is it any good?