I have the Mountain Buggy and I can put it up with one hand (but you need two to collapse it). For me, how many hands it took to dis/assemble it never played into it as I figured that if I was driving somewhere, I would leave DD in the car until I had the pram ready for her and when leaving, she would go into the car before I tackled putting the shopping and/or pram away.
The Mt Buggy weighs less than 9Kg (I have the Urban Elite) from memory. We bought our pram for its weight (amongst other things) but I do find the width can make it a little challenging to lift in and out of cars... even my friends 4x4! But I do love my Mt Buggy!

HTH

MG