i can only speak on the SX.
Pros- casts like a rocket, really smooth, light, can get in high speed gear ratio, looks good, iv thrown everything on it from weightless senkos to 5 inch swimbaits. I love it, I use it more than any other reels I own.
Negatives- extremely touchy. For instance, I can make 100 flawless casts and then itll backlash on me. My S's, Premier, and MGX do not do this. The upside is when this happens, the backlashes are very minimal. I could not throw fluorocarbon with this reel. So I had to switch to braid.