Color me impressed. At first I thought this would be a really bland filler of just Spoink searching for it's pearl, but it got really good during the second Act.
I mean LMAO, they actually gave the Magikarp salesman a back story?
His 6 kids all had the same nose. It's pretty cool to see such a minor character like the Magikarp salesman actually given some character development, and I love that 4kids remembered his voice.
It was also pretty cool to see Giovanni at the beginning of this episode. Giovanni is way too forgiving to TR, their Skiploom secret base gets destroyed yet he doesn't seem to care much. Maybe he just wants them out of his hair? Likes the Butch and Cassidy reference too.
And the Trainers choice was actually right this time! Good job 4kids for picking Steelix to use against Electabuzz.
This episode also had stronger continuity than usual, such as the Magikarp salesman and TR remembering the Feebas from the Wishcash episode. Thinking about it, it would be pretty cool if TR had a Milotic.
Another good part of this episode was the neglected pokemon finally got some screen time! Torkoal, Dustok, and Mudkip all got some much needed time in the sun. Brock actually did something in this episode, but of course since he took an active role May had to be pushed into the backround for this ep.
Overall a very good filler, I actually thought it would be really bad at first but they turned it around very quickly. I'm impressed.