Generally speaking, somebody with an Amazon zShop is going to be fairly reputable. I manage an e-commerce development company, so my clients are those small e-commerce merchants that y'all are afraid of.
I promise, there's nothing sketchy going on at any of MY clients' sites! Even so, many of them keep Amazon stores or Yahoo stores in addition to their own sites, just because the name association and appearance of security and reputability is so valuable.