Richardson ridicules the show's new boyband, Union J, while Lock complains about the contestants' claims that the programme is life-changing.
"The contestants say, 'This is a life-changing experience'. Haven't you seen the show? Even if you win, by February nobody knows who you are. At best, it's a gap year from Argos," says Lock.
Meanwhile, Richardson brands Louis Walsh's Union J, "A Slightly Different Direction", mocking their similarity to the show's previous boyband stars.
Guests on this evening's show include Heston Blumenthal, double Paralympic gold medallist Hannah Cockroft, Josh Widdicombe and Katherine Ryan.
8 Out of 10 Cats returns tonight at 10pm on Channel 4.
New! Digital Spy breakfast show - watch Anna Williamson discuss the day's biggest stories including The X Factor, Homeland and Leona Lewis: