Hi there -

Just jumping in re Downtube. I have just had a very bad experience dealing with them which I won't go into in detail. In brief, what pertains to your question about suspension though, is that there is a front suspension only model on the site is the 8H but it is, I believe, heavier than advertised. They tried to tell me that all foldy bike manufacturers posted bike weights wo/seats, pedals, etc but I didn't find that to be true, but I did find the 8H to be heavier than expected and heavier than advertised (by my scale it weighted 34lbs rather than the 26.5lbs).

The Downtube was a little more solid feeling than the Citizen but I think that solidness contributed to the unexpected weight.

About your budget - there seem to be Citizen and Downtube and maybe a Dahon below that and everything else is above (or at least the one's I was researching).

I ended up with a Citizen.