laura marlin mysteries/books for eager 6/7 yr olds

[thewalrus]

Hi all
Just wondering if anyone (anyone's children!) has read these and what you think. I'm looking for books for nephew (7) and DD (6) - both good keen readers. They've read lots of Famous Five, Harry Potter and DN loves the Enid Blyton 5 find outer books. DD has just ready the first in Helen Moss' adventure island series and really enjoyed it. Do you think I'm on the right track? Any other suggestions?
Thanks a lot

[PolkadotCircus]

My son likes them,has been reading them since 7/8.

[thewalrus]

Thank you!