ESF Schools vs RC

I don't know exactly the difference between the ESF Schools and RC. However, I learned that a lot of my friends chose RC than the ESF schools (like BHS, Shatin Junior, Kowloon Junior) when their kids promote to Primary school.
Anyone can give some comments to compare the difference between the schools I can only give these:

ESF: $2K cheaper tuition fee, simplified Chinese
RC: $2K more, traditional Chinese


Please add on based on your understanding. Million Thanks!