Spagg, I had a couple of goes at it and managed to elicit a correct result but if I was here until Christmas day I would never have identified the reason. Two good rows for me two not so good rows.
Thanks.

I got the rhyming slang group, and I figured there was a Boomtown Rats group, but didn't manage to complete it.
Hard grid.

Complex and challenging; good grid.

Got one. War. But even that should have had the clue 'Edwin Starr song'. I think you have good ideas for groups but the links are often not direct enough to give people a chance of joining the dots. It's not enough to just stick down a clue that has a tenuous or indirect link to the group at hand. Maybe that's just me... but I think that's the quickest way to get higher ratings on your grids if I'm being brutally honest!

Thanks for the feedback; i'll hone things as best I can.

This trying to please everyone malarky is a bit tricky tho!!

Thanks all.