When I picture 'mumsy' boots or shoes it would be something flat, practical, probably fur lined, laced up, and waterproof... maybe in a 'quirky' colour or fabric. Nothing wrong with that but it's basically the opposite of these!
I have a similar pair (from m&s) and I like them. They're classic and I'm reasonably sure they're currently considered stylish, as I've seen them featured on Who What Wear and similar fashion blogs for a while now. The Cos ones are more fashion forward, but I think that curved heel would date them quickly.