Personally I consider lots of factors,snacks are they healthy,staff,are they friendly? Are the toys suitable for ages of children who attend? and then distance plays a part for me,as picking 1 up from nursery at half day can be tricky.
I attend 2 mother and baby groups,both cost £1 which you cannot beat on price,they run from 10am til 12pm and have a range of activities for the boys,my gripe is biscuits are offered as snacks
but alas I'm guessing they are volunteer groups and they'd have to charge much more fo a choice of snack,which may limit their numbers,so I just take a banana with me!!!!!! They are more than happy for me to do this,think that's because I make the cakes at christmas and easter!!!!!
As for playgroups where you leave your children.....anyone who's aregular will no I'm not afan of doing that and very fussy about snacks,activities etc.....Jc wont be attending one,he can go to nursery at school at 3,that's plenty soon enough I think!