[Fish Sandwich]

Gosh I wish I could help more with this. I've seen about half these shows and like them but I'm not sure I could really name a particularly good episode from memory. These'll be more episodes that stick out to me personally than anything.

Magiranger:
I extra don't now what to say here. Magiranger's greatest strengths are its sense of continuity, character development, and pacing, none of which would ever be apparent from a single episode. I will say I checked out episode 15 first, since sometimes I like to watch a random episode of a Toku show I don't really plan on getting around to. Clearly it didn't turn me off the show.

Go-onger:
Go-onger doesn't really vary in quality that much episode to episode so any one is a decent pick. Episode 5 was an early stand-out to me though. It's the first episode to focus on Go-on Green and I think those episodes tend to be extra funny.

Ninninger:
Episode 11 has a fun meta sort of plot about one of the mecha feeling left out of the action in favor of newer toys. It's really representative of Ninninger's quirky sense of humor and it probably also shows off the almost Tsuburaya-level practical effects it had for the mecha scenes. Ninninger left even me burned out by the halfway point but I still think it's kind of underrated. A very fun show in general.

And if we're allowed to shill our personal favorites:

Episode 7 of Go-Busters really gives a clear picture of the unique Sci-Fi/military(ish) style the show had and, being an episode of Go-Busters, is generally awesome.

ToQger is a great show that had a really rough start so more than a lot of shows here it's a good idea not to judge it based on its first couple episodes. I'd recommend episode 10 as being solidly representative of the show. It's not too different from any other episode but it was the first time the show used its "imagination" theme to have a good message.

Hope any of that helped you!