If you recall, I only got 2 of the Sidekicks via the original Frito Lay promotion. Luckily, thanks to this 2nd Round of GameStop bringing them back I now have the complete set.
The Sidekicks really add nothing to the gameplay...they just hurriedly follow you around often provoking laughs or comments of, "How cute!" from others. I have gameplay footage of Terrabite and Trigger Snappy up in the SSA Playthrough...I'll try to record all 4 in action soon on the Giants playthrough.
The promotion that helped me land the little Skylanders is going on at GameStop through the end of May 2013...If you need anything I'd pick it up there and land the FREE Sidekick! Good luck!