What is better for ESTABLISHED small and mid size online retailers: All-In-One SaaS ecommerce suite (e.g. GoECart 360, NetSuite, etc) or loosely integrated shopping cart (e.g. Yahoo Stores, Volusion, etc.), order management system (e.g. OrderMotion, StoneEdge, etc.) and shipping software (e.g. Shipworks, Shipwire, etc.) from multiple vendors?
What other solutions are TRUE all-in-one, end-to-end besides redprairie, goecart and netsuite?