I've been meaning to get to this for awhile, but almost two weeks ago I bought a Dahon Speed P8 from Thor (brakemeister). Here are a few of my thoughts and observations from the first 40 miles or so (I'm training for a marathon so not a lot of time for riding unfortunately).
Without looking down it's hard to tell you're on a small wheeled bike. The headset was a little on the tight side, but after adjustment handling was snappy, but stable enough at higher speeds. The positioning is a lot more upright than I'm used to, but a quick saddle adjustment made it comfortable enough for at least a 10 mile ride. Adding Bar ends in the future might help with that a bit.
After a fair bit of adjustment everything works great!! I did immediately switch out the stock gripshift for a suntour friction thumb lever, as well as a set of (very similar) Bontrager grips. Again after a bit of tweaking, shifting is quiet and crisp, and I don't see any reason to use the dérailleur tab on the frame any time soon. Also I don't really see any problems with paint abrasion when folding. Its just a little dirt here and there mostly, and any small scratches can be covered up with a sharpie pretty easily.
I also added fenders and MKS EZ Promenade pedals(with Powergrips). The pedals are great, they fit easily in the seat bag Thor was nice enough to throw in (thanks again btw). I have yet to have any problems with the pedals coming undone, but I keep the plastic locks in my bag for longer rides.
The Schwalbe Big Apples are great tires, and don't slow me down in the least, in fact I set a record commute to work the other day (Previously held by Surly Steamroller fixed gear), of a little over 12 minutes for 4 miles (counting lights and intersections!!).
I've already found this bike to be very handy, as it fits perfectly under the coat rack at work. After my first commute it rained almost immediately, and it was nice to hear the rain on the roof at work and know my bike wasn't being soaked outside. Its also nice to be able to put the bike inside a vehicle, and not worry about theft or tampering.
As with any stock, factory adjusted bike, if you want everything to work as smoothly as possible, it needs to be looked over and tweaked by hand. Most dealers offer service to inspect and adjust the bike for you, and it is well worth it if you are not the hands-on type.
Out of the box I adjusted the shifting,brakes,wheels,saddle position,headset,release levers,hinge,checked screws for tightness,oiled and lubed, etc.
Also a huge thank you to Thor (www.thorusa.com) for his help and excellent service. Despite the fact that I missed his email and arrived later than I should have, he spent over an hour with me to make sure I got the bike that fit me best and was what I wanted.
I had informed him of my worries about fit (I'm 6'4"), and he had two bikes set up differently to assess any issues. It was definitely worth the 140 mile drive to see the bikes and parts in person, especially since I had no experience with them.
I expect this to become my main bike, at least for shorter rides, even after the initial novelty wears off. Thanks again to Thor and the forums, both have been really great resources that I will continue to make use of.