You definitely want the SWG turned off when the pump is off. However the timer works it is simple enough to power the SWG from the same switched line the pump is powered from.
The Intermatic mechanical times are inexpensive, extremely reliable, and just about fool proof. Not all of the digital timers are worth the extra money, though a few of them are quite nice. For a simple setup, such as yours, I would tend to go with a mechanical timer.