Could I step in with a few comments? I have no ties to Downtube, EuroMini or any other folder or company, so my thoughts are strictly my own. I've got at least a couple dozen folders, and this is what I've learned.
First of all, I'm price-sensitive just like anyone else. So I get the idea that in a relatively inexpensive folder, there are going to be compromises. Freewheel vs. cassette is one. I'm sure Yan would love to throw a cassette into a $300 folder, but...
I don't think the general public realizes that designing and engineering a folder is much different than a non-folder. Not only do you have to make the folding bits work well together, but you have to make the entire bike safe to ride, hopefully long-lasting, and easy to fold/unfold. So much more money goes into the frame than a non-folder, which leaves less $ for components. We would like Yan to stay in business, so he does get to make a small profit, right? If he doesn't, what's the point of being in business?
On the freewheel vs. cassette issue on a folder, this is of course a consideration, but much more important to me - especially in a relatively inexpensive folder - is the issue of how well does the bike ride, how well do the folding bits work (play in hinges, ease of folding/unfolding, etc), and are they prone to excessive wear. All those issues are of primary importance, with parts selection being a secondary consideration. Not that the freewheel vs. cassette isn't an issue, but we're not talking about expensive folders here. It's unrealistic to expect high-quality parts on an inexpensive folder, all else being equal, unless you like having problems with the folding bits or the ride in general. There is no free lunch in folders. You get what you pay for.