Nothing wrong with the Brompton, I’ve got one (as well as Stridas), and on paper it ticks all the boxes, smallest folded, great quality, choice of gears etc. But I just prefer Strida - Its something about its simplicity, single speed belt and all - it just feels lighter in every sense, more fun less serious.
I only tend to take the Brompton when it has to pack into a small rectangular space, its best feature - but then I miss the better roll-when-fold of the Strida.