For my money the absolute winner in the category, as well as easily one of the safest designs is the Börner V-slicer, reviewed here on Cook's Illustrated.
And here is even a video review on America's Test Kitchen:
I consider this a pretty good review. I have owned two V-slicers over the last 40 years, and I have used other people's mandolins, but for me the V-slicer has always been the winner. Some of these mandolins actually make me scared from a safety standpoint, but the V-slicer is very safe to operate, although you must always be careful with sharp knives, not only to protect yourself, but also to keep them sharp longer. So grant yourself a Swissmar Börner V-slicer, and enjoy. It will make you an instant champ with vegetables, and able to make any number of fancy salads with some ingredients that might seem unwieldy otherwise.