You need to give more info. There are so many "best" lifts for different purposes.
-What size tires do you want to run and how high do you want to go?(these two go together as one will answer the other)
-Do you drive on the street most of the time?
-Do you wheel at all?
-What kind of wheeling do you do?
-How much does price mean to you?
These are questions I would suggest you ask your self and then you can narrow things down a bit.
For Cheap, i would recommend Rogh Country
For the best for the money, I would say BDS or Rubicon Express. I have experience with the ones listed, but there are many more. I know nothing about Superlift and Skyjacker except they cost more. Tuffcountry is another. Rancho makes lilfts for the YJ's, and the list goes on and on.
Old man Emu is a small lift, but rides very good, and is nice for 31" tires