I'm retired now, so don't travel the country with my folder any more, but for over ten years I trained and biked to training venues everywhere. I used a City Express, a 7 speed, ally, 16", mid folder which didn't take up much more space than a brompton. But punctures were no problem, and maybe less frequent because I could have 1.9" all-terrain tyres which probably handled bumps, sharps and ridges better. I never found out if I could take it on the London Underground because I cycled between main-line statrions so easily and quickly, so that's what I did. And the City Express, when unfolded, has a neat flat bar which I could sit on if all seats were taken!
It was a great folder, and I never felt the need to follow the favourite, but there was one aspect of the City Express which beat the Brompton....... it cost £169 with £10 for delivery. Now this feature removed any feelings of worry because I could lock it to a bike stand, go shopping (whatever) and forget it, because Bromprons might get nicked, but City Expresses don't because almost nobody knows about them.... no 'must have' aspect. And it was small enough to come with me into training and hotel rooms.
I changed it last year for a City Zoom, described in folder reviews as 'very odd', but this happens to ride beautifully and is better for me because I can bend the bottom bracket bar partly and reduce the bike's length by a couple of inches so that it fits in the plasti-bin outside my home. I chain bolted to thr bin's floor is its security.
Bromptons are without doubt the A+ folder but they don't do well on unmade or rough roads, or soft ground, have increased security risk because of their popularity and cost more than five (or more!) of my folder.
Call me cheapskate if you like!