A big topic.. maybe a few specific questions would help you get better info?
I hinted at my main issue with small-wheel folders in the other thread, that they can be a bit twitchy feeling and the small wheels don’t cope with city streets as well as a bigger wheel. But that’s a fair compromise, no real problem once you’re used to them and they are transport rather than performance bikes. Fatter tyres and rims wold help. Or the suspension of a Birdy. But overall, not going at top pace around town isn’t a bad idea, drivers usually see a bike and think ’10mph’ and manouver around you based on that.. if you’re doing 20mph+ it can be interesting..
But with train companies limiting rush-hour travel with bikes to small-wheel folders, that’s the way most will stay in the UK if they’re bought for train+road commuter use.
I wonder if Moultons could be made to fold rather than just seperate, without compromising the ride. That could be a great city bike.