Nice grid! Not sure if Roger Berry is famous enough but he was an MP for a long time, the Berry group could be all famous Rogers!

Really nice. Thank you. Nothing too obscure to work out, nice logic to all the links, and fun red herrings. @EddieCrane if it HAD been a famous Rogers group, I'd have been lucky to get it, and it would have been pure guesswork, as I've only ever heard of one of them as a famous Roger, and it's not the one you mentioned - literally never heard of the others in any context.