I am a CM BTW.
I would choose a CM because I like the idea of children being in a homely setting looked after by a 'mother figure', and to be able to form a good bond with one person (I found the nursery I worked in had quite a high staff turnover and staff switched rooms regularly).
I want my children to experience life in the community, go to get groceries (small daily shop- they can get so much out of it - counting, learning new words, choosing what they want for dinner, learning where food comes from) go to the library, go for walks, feed the ducks, go on trips and go toddler groups and CM network groups.
CM now have lots knowledge and good resources and know how to use them to make sure children are learning through play. This is due to being able to access the same training as many nursery staff.
I wouldn't mind if a CM has her friend /sister/ Mum round for coffee occasionally as long as my DC was entertained and not totally ignored! It's nice for children to meet other adults and their DC's.
(I haven't done coffee with friends as a minder but my relatives do pop in and make a massive fuss of my mindees which makes the mindees day.)
The downside of choosing a CM for me would be finding cover for times when the CM or her DC's were Ill. But this would be less important than them experiencing the whole package a CM has to offer.