The core gameplay is satisfying at first. You can slow, stop, or rewind time in small chunks, and the otherwise basic combat is enhanced because of it. Catching bad guys sitting in their chairs at evil work, then pausing time, putting two pistol bullets in the back of their heads, and resuming time only to see them drop dead instantaneously is a sadistic treat.
The fast recharging times on your suit also do a good job of encouraging frequent use of your abilities, and the basic puzzles pop up often enough to actually force you to go 4D. Unfortunately, both the time powers and puzzles are lacking in variety. Most involve pausing time to sneak through spinning fan blades that would otherwise tear you to bits or one of a couple other basic formulas, and they never challenge you to incorporate more than one time element.
TimeShift is also guilty of being all-too-formulaic. You'll run into your standard vehicle and gun-turret levels in the middle areas of the game, which do serve to break up the action, but not in a way that's more fun than what you were already doing.