SIA is a great solution for those clients with issues surrounding excess stock, stock shortages, needing forecasting especially with new product launches or retirements. In addition to what @JohnHoyt mentions, as I've worked on 3 of 4 installs of SIA, the customer's expectations need to be identified first, the data clean up is mandatory and the purchasing staff, and if existing manufacturing staff, have to have a clear idea what this product will and will not provide. As I've worked very closely with NetStock I'd add that changes are added to the product nearly daily and so when supporting this, you'll need to visit the customer's SIA or the demo SIA site frequently. Also, I've run across issues with the coding in SIA and worked with NetStock to correct the issues. One more thing, if your customer has a specific need, such as a seasonal calendar, integration with work order, or other modules, limitations on warehouses included etc. that these can be customized for the customers particular needs.