I haven't tried a vstore but I do use eCrater and I like it.
My guess is that either would be fine for sales but the trick is that you have to advertise and promote like crazy to get people there (because there's not such a built-in customer base like eBay has). Of course, eCrater (maybe vstores, too, I don't know) uploads all of your products to Froogle so I know I must be getting traffic from there.
I haven't gotten a ton of sales there (but I sell to a niche market anyway) but they're pretty nice when they come. When PayPal fees are the only fees you have to worry about then it seems like nothing!