maybe I'm just too avid a diy fan but for me, it made no sense to buy what you can easily make for less than half the price. there are tonnes of clear and useful internet guides to making all sorts of mash tuns, from steel to coolerbox to plastic insulated bucket, and my guess is people who want to move to all grain will build their own. To be honest I think what you need to focus on is offering things to people who are already brewing all grain.