Quick disclaimer: I'm not going to assume anyone will have the same experience as me, nor will I believe anyone was expecting to feel the same way we all felt when watching Scooby Dooby Doo Where are you. Of course. I was watching it when I was a little child, in the mid 2000s.
Having said this, it's impressive that they have managed to get such a high quality episode with such a low budget.
Nevertheless, the story, at least, wasn't so quite impressive. The cliché good outsider guys vs the bad bullies in the school, is definitely a motive of this story, as you can see in many many many similar tv shows.
Some special effects were good, others were mediocre to bad, but that's to expect on $20k episode.
As a conclusion, I'd say it's a solid 7, perhaps even an 8.
Note that obviously those numbers are relative to all the other tv episodes I saw, combined with their average rating.