I think it depends what you want. Nipper is lovely to push but a bit big and clumsy folded. Baby jogger city mini double looks nice & folds easily but it's a bit wide (shopping basket is fab though nipper basket isn't as good) and the phil and teds (dot) is lovely and compact, great for city centre and small shops but no basket when the bottom seat is in use. I also didn't like it for newborn/ toddler but it's great for older baby/toddler.
Those are the 3 I have owned and I have to say, the nipper is my favourite but I walk a lot and never tried to get it on a bus. Got phil and teds on bus several times, very easily