I have the Workswell 125 which appears to be the same frame. I've got ~400 miles on it so far (including some rough terrain on the DK200) and it has been great. The seatpost clamp design is a little weird. It uses a little compression plug that is recessed into the top tube and sits in front of the seatpost. In my mind, it seems like a better design than the standard collar that is used on most bikes since it distributes the pressure across a wider section of the seatpost.
Here's a really bad pic - please forgive the dirt that I have yet to clean up after the DK
