Worst - some hand me down 185 Blizzard's from the 80's I got from a great uncle when I was like 13. They were as straight and stiff as 2x4's, but I learned 360's on them.
Best - OG Fujatives (red ones) or New Life's. Those Fujatives were bombproof and SO soft and buttery. Made for a really good time in the park, but kind of a pain in the next everywhere else. New Life's are stiff, but playful and super fun in almost every condition. Used them as my daily driver the last couple of seasons. I'm getting out on my new Jmo's for the first time on Saturday, so I may have a new 'best' ski pretty soon if they live up to the hype.