Borner V-Slicer. $40. Maybe a $200 - $300 mandoline would be better, but for that price, I'm not going to find out. Even with reduced dexterity and strength, I have no problem with the Borner.
USE THE SAFETY HOLDER. It is eminently easy to use - if I, who have trouble holding on to a knife, find it easy to use, trust me, it is easy to use.
I only wish I'd gotten one sooner - I've always been, shall we say, CAUTIOUS about mandolines. The Borner is really really safe, works very well for everything I need to do (including making very fine matchsticks of ginger, something that easily clogs up most shredders and graters). I've got most of the stand-alone graters and slicers as well (like the curly slicer), also extra inserts for the V-slicer itself.
I got the "classic" version, not the pro. The Pro/newer versions have higher sides and leave more waste.