If I would rank them, it would honestly only be like 3-4 sets: 1. Gorgon -- best defense in game and stamina regen? yes please. 2. Lynx - Speed increase will be the difference between landing and completing a combo and stunning and enemy or taking a hit. 3. Black Cerberus -- Damage increase is great. Makes end-game less of a slog while giving you better fighting chance at NG+ 4. Liquidator -- Immunity to toxic puddles and gas is all there is to it. I feel most every other set is rather gimmicky or doesn't have the pure awesomeness of the above sets. Take Eagle set for example; gives bonus charge to each reusable. Sounds great, right? But then why not just equip another set of estus flasks and get a set that gives you some combat viability? Rhino is beginner's trap set, lol.