Kerry-Anne and I had breakfast at the hotel - and while the food was perfectly good, and the service impeccable, I wouldn't recommend it as a place to have breakfast unless you're actually staying in the hotel. The breakfast area is tucked away inside the hotel, with no views to the outside - and there really are plenty of places in the area with far more beautiful views.
Still, even though the breakfast spot isn't wonderful, on the plus side, I think Winchester Mansions will remain my favourite place for Sunday afternoon tea and scones!