We've gone for the P&T but our age gap is going to be smaller - my DS will be 23 months when #2 arrives. We borrowed a friends P&T a few times and tried DS in the front and the back and he loved both options. He's generally fairly easy going, sometimes kicks up a fuss about getting into the pram after he's been running around on the loose

but will happily spend half the day out and about with me at the moment, so I'm hoping we're going to get a lot of use out of it
Our friends have decided to go with the buggy board option first - their age gap will be more like 28 months - as that's cheaper and if they find their DS can't/won't use it then they are going to buy a P&T or similar then.