ISIS drivers are sable but so is good Twaindrivers also. Twaindrivers for “professional” scanners are stable and good. No limitations in Twain, just how much work the manufacturer puts into the driver. Usually there is no problem controlling all features by Twain, specific features are controlled by custom capabilities. Twain has often a bad reputation of beeing less stable than ISIS but lokk at it this way : The unstable Twain drivers with little funtionallity is the low-end scanners like you buy in a shopping center and there is no ISIS drivers for them. So basicly, profesional scanner you can use either Twain or ISIS – your choice. Then you have the 100s or whatever scanners where you have no choice – only Twaindrivers exists. And have you ever seen an ISIS driver to a MFP (copy-machine) ? Possible there is some but I have never seen any. New MFPs will have high-speed scanning (dual sensors for duplex scanning) and customers do not need to buy an expensive document scanner – they can you their MFP in the future.