I sent my son Sid to Jo a couple of times over the summer and she was absolutely fantastic with him. He was very teary going in to her house (he didn't want me to work again) but Jo and Lily did everything they could to make him feel like part of the family and to cheer him up. By the time I went to pick him up, he didn't want to leave at all.
I am self employed and take my son around the country with me often for work and I use many childminders (so I know what I'm talking about).
Jo takes the kids to lots of different places, she is friendly, kind and very accommodating. I would definitely recommend her. If I lived in Cambridge I would use her all the time.