Not one concern
My son (coming up to 5) has been going to Chris and Rachel in the school holidays and days like voting days when his school is closed. He can normally be quite shy but was completely at home as soon as we went in.
He is excited to go back and thoroughly enjoys his time there. I can be quite anxious about how he's getting on, but they send me pictures and updates about how his day is going. They feed him whatever he likes and he doesn't come home hungry. He loves their pets and genuinely enjoys learning about them and how they behave.
I genuinely can't recommend Chris and Rachel enough!