And the Brompton S is stiffer than the M and all Brompton models have suspension.

As for the complain frequency, I doubt that this forum has x40 Dahons than Bromptons.

My main complain about Dahon is the post sales support. The company will not even talk with you (try to find their phone number, same applies for Tern) and propriety parts are difficult to find. At one point I looked for a Mu P24 Dual Drive left grip shifter and even the Good Dealer could not get it for me. I got the phone number of Dahon NA and talk with a guy that could not care less if the part is available or not. At another point I needed a plastic chain cover for Vitese IGH, eventually I got one but had to file and drill it to fit.

Compare this with Brompton spare part availability (online ordering, shipped worldwide) http://www.sjscycles.co.uk/brompton-shopbrompton_pg1/ They even give us the part numbers. Try to get this from Dahon.

As for Tern, they promiss to have better post sales support but I did not see a phone number on their web site and this thread suggests that they will not have Brompton style online ordering by part number (see how Josh Hon avoids the part of the question about online ordering)
http://www.ternbicycles.com/forum/wi...-parts-problem

I got a Brompton S 6sp for special occasions where I need small fold and pretey much it became my main bike (replacing the Moulton TSR 27). I like the ride quality and have no problem doing 15-40miles rides.