Speed: The print was ready after 2 days. The transport agency took additional 3 days, so I received the parts within 5 workdays after the order.
Communication: I did not use the service of Treatstock before. So, I was surprised to get a photo of the pieces after the print. This is a helpful feature. I did not have contact to the manufacture company.
Quality: I think the design of the part is one of the major premises for quality. One type of a part was printed mostly correct. Some edges were a little bit roundish. I could correct it with a rash. A second part was not printed as expected. A 1 mm hole in a cylindric body appears only at one end. I guess the printing process is not suitable to produce this part as I have designed it. This might be caused by my limited knowledge of how to design a part for 3D print.
Nevertheless, the whole process was smooth and easy to use. The result will not prevent me from using it again.
Printing started the same day that I ordered, just a few hours later. Received the whole set of ordered prints three days later, carefully packaged. Good quality prints, little to no need for additional sanding etc.
Randolf Leipnitz, Holger Kuznik GbR 
