A friend is trying the Joomla/VirtueMart combo. She likes Joomla, but deleted VirtueMart stating that it's more difficult than it needs to be. She switched to OSCommerce.

Another seller I communicated with recently was dissatisfied with VM's depth of subcategories which caused problems organizing a variety of tee shirts.

I installed, but have not yet worked with Mambo on one of my sites. I'm partial to ZenCart and will be trying that combo later this year or early '08.

Meanwhile, I'll be interested to read other people's experience on the Joomla/VM platform!