This paper describes the key elements of usage and implementation of AI-based tools in a real product design environment. In the past several years, the authors have developed several intelligent programs to empower mechanical engineers in the product design of personal computers. The programs focused on plastic material selection, snap fit design, design for assembly, design for service, and design for injection molding. Engineers used the tools initially as training tools and then attempted to use them for real design tasks. Some programs received long term acceptance and usage by designers, while others did not. The metrics for successful development of the AI-based tools do not coincide with successful implementation and usage. This paper briefly describes each of the programs, takes a critical look at their long term utility, and seeks to extract the metrics behind successful tools in practical product design.