I generally agree, Zizzo does look like a great value in a bifold. And for me, occasional folding, it would be great, although most of the difficulty in folding my bifold is taking off the panniers and trunk bag. But even then, it carries poorly. For someone doing frequent folding (like daily commuting) and carrying up stairs, I think the Brompton design is superior, though it's still a pretty penny for the genuine item; But for a clone now that the patents have long since expired, at 1/3 that price, I'd get a clone for commuting if I needed it. Especially if by forward-seated train, so I wouldn't need to leave the bike in the luggage rack where it could get stolen at a stop. With no train or bus, if I could carry the unfolded bike up stairs (easier, the forward hand can share the weight), or use an elevator, and could lean the bike in or outside my cubicle, a bifold or any other bike would be fine. For air travel, a 349 trifold is superior.

Any bike shop that stocks both 20" bifolds (any brand) and Bromptons, try carrying each one folded. Quick test. Then try riding.