Stover's written what a lot of people agree are the three finest STAR WARS novels of all time (the RotS novelization, TRAITOR and SHATTERPOINT). He's also the author of a very highly-regarded SF/fantasy crossover series, THE ACTS OF CAINE (I'm due to start reading this soon). He's very, very highly regarded critcally.
Brooks and Salvatore are not, to put it mildly. They're popular, sure but the last good novel Salvatore wrote is 20 years old now, and Brooks (though he's gotten better over the years) is still writing generic, MOR, unexciting stock fantasy at best.