Titleist has dominated the PGA tour for years, but Taylor Made has started to make strides with their TP5 and TP5x balls.
The Callaway Chrome Softx has recently started to land professional players, and a few have recently moved to a Srixon ball as well.
The best ball for you does depend on your game, but if you want to play the balls played by professionals, you may want to stick with Titleist, Taylor Made, or Callaway.