Thanks for the helpful replies so far.
I'm not sure I get ecommercetemplates, but I'll try looking at it some more. Their website is less than enlightening.
ShopX sounds like heaven, but alas won't be practical for me to deploy in a short timeframe. And i need to sell a lot of things and integrate with a retail store POS, so that adds complexity that ShopX may not be ready for.
Is it not disconcerting that cpCommerce is two years old (almost exactly two, in fact)? E-commerce has come a long way in that time... or has it? Anyway, it seems like a dead project, no? I need to use LinkPoint, and I'm not sure I can do it from scratch (I know what an API is, but I am not really much of a programmer).
I'll give ZenCart a closer look. The things I disliked most about osc were that step one is to turn on register globals, and that overall it is just a mess. As others say, content and logic blend in a very sloppy way. Oh, and the fact that there are over a thousand modules is actually a down-side. There is no way to evaluate them, and no way to really know what all is possible.
The system I'm next going to try is
ViArt. I have just found it so dunno how much it will irk me when I play with it; but I do like the idea of an integrated CMS. And the product display logic seems pretty sophisticated.
That's where I am now (sorry to be a downer, but hey, MODx has really raised my expectations

). More suggestions are very welcome, and I'll keep this thread posted on what I learn.