Bernie, surge protectors, regardless of the price, are a good thing to have, especially one with a ground fault indicator. However, keep in mind that no surge protector can survive a hit from a lightning surge that hits nearby - NONE! Therefore, the protection is modest at best, but as my wife says when asked "how's your husband?" She usually replies "Better than nothing - but not a Hell of a lot!"
As for the APC, well, they too are marginal at best, essentially designed for computers so there would be no loss of date during a brief power outage. The one you listed is just 330-Watts, which would handle a small PA system and your keyboard for about 30 minutes at best. Of course, if power was restored during that time, the system would revert back to wall outlet power and begin recharging it's internal batteries.
Hope this helps,
Gary