There have been a number of instances where I found smaller wheels to be an advantage, especially when navigating crowds (well, pre-pandemic). And for the most part, they're just fine, barring rough rides or steep declines/inclines. Of course, the premise of the Helix is that you can get a much larger wheel size into a comparably smaller form factor fold and corresponding weight. For the most part, it succeeds - it is larger than my Brompton, to be sure, but not dramatically so, and weight wise, about the same given my Brompton configuration. However, folding bikes are an exercise in compromise and tradeoffs. The Helix is expensive, is unique, and might not do it for everyone. I'll leave it to RatonLaveur and others to decide what their tradeoffs are.

I agree that the Brompton hinge is reliable. I've never had an issue, and I've hauled this thing on flights, banged around in its case, towed a heavy kid trailer, and ridden it up a hill that it probably wasn't meant to go up. Arguably a solid, "unbroken frame" is stronger inherently, but the Bromption is certainly more than up to the task, extreme cases notwithstanding.