I have the Valco Run About and use the toddler seat which can be collapsed when not in use.
Had it since DS1 so that's 6.5yrs and the toddler seat we got when I was pregnant with DS2.
It has technically been through 4 kids as when DS1 was younger and DS2 wasn't here yet the toddler seat got used by our lovely niece on a weekly basis.
This pram goes outback! My DH runs with DS2 and DD in it and has ran with it with all kids.
When we had DS1 we only had one car and I walked every where. It is very easy to push, effortless.
Only problem is it doesn't fit through a normal size supermarket aisle, have to use the extra wide aisle.
I have used it for DD since newborn, so it works for all ages. They may have improved even more since we got ours.
Oh, and the nappy bag goes well over the back without hitting baby in the head. You could also attach a mummy hook if you really wanted to carry a few extra
bags and I have also attached a drink holder to mine as well.