I acquired the recently released GuardSharp by lansky. This provides 4 fixed angles to choose from in a very handy and protable unit. So far I've only used it on smaller blades, i.e. pocket knife blades. It provides an excellent edge achieved with little pressure. A ceramic stone is also provided, shaped in such a way as to enable sharpening of serrations.
"Life is good if you don't weaken." AG Russell