I have had really good luck with the Spiderco Kit i picked up at cabelas. It does need frequent cleaning with a scotch pad and some Comet cleaner.
If you know the angle of the edge, it works fantastic. Versus trying to re-edge a blade.
FYI, Gerber knives are sharpened with a uniform 15? angle on each side for a total of 30?. At least my LMF II loves the 30? setting on the spiderco sharpener.