Nicola The thing about a P&T that i can't get over is how boring it must be for the sibling in the lower part of the pushchair. I'm also not keen on them being so close to the ground. I mean what if the paths all dusty, or gravel gets flicked in, or they get splashed in puddles etc. Also you can't really see them too well when pushing as they are at your feet.
I think the size of them is great so they must be great for shopping and easy to push.
Just had a look at the nipper and like the 3 wheeler aspect and side by side element(both being able to see out, see each other etc.) but just seems too wide for me, it would be wider than my quinny which often bangs into stuff in over stocked shops. But can see it being lovely to push on walks.