Any skit Silver Quill does. He goes beyond simply reviewing the episode and uses his OC to actually act out skits, interact with other characters from the show, and they're all very funny!
Also the various skits and reactions with Brawny Buck
Strebiskunk's reaction to the toy-bait helicopter in "Testing, Testing 1, 2, 3".
Strebiskunk: Maybe you can figure something out after this commercial break. (helicopter flies by) Seriously, I cannot believe they actually got this toy on the show. I especially like Cherry Berry's expression here. It's like the animators are saying, "Okay, Hasbro, here's your advertisement. Are you fucking happy now?"
All of TBBBAP's videos are extremely funny, mainly having to do with the brotherly chemistry they have and how they work together so well! They always try make a unique opening to each of their reviews, which are often parodies.
Most of KP's comedy, but special shoutout to her "relationship" with Meghan Mc Carty and the animatic segment of "Let's Go and Meet John de Lancie".