I have several friends who have PnTs and they love them. I don't really like inline prams at all, I feel sorry for the kid stuck underneath! The MB duet is a really narrow double, I'd highly recommend checking it out.

I don't think the Graco would work well without a capsule for a newborn and small/young toddler. There is a few tandem strollers like the ZuZu Evolution or the bootiq deux which will take a newborn and toddler and fold quite small. I've not tried them though.