All of them are good slicers and I think it depends on what you are trying to do as well as your skill level. Real makers will other slicers than beginners who will likely enjoy the simple user interface of Cura.
Another factor is the 3D printer you are using, Flashforge users might even prefer the Flashprint Slicer as it perfectly integrates within the ecosystem.
RE: Which 3D printing slicer is most popular in 2018?