When going through product reviews and user feedback on the existing UM2 model as well as suggested points of improvements for future models, the following issues always come up in the top 3:
feeder system problems
nozzle clogging problems
In the case of the feeder system for example, some reviewers state this is an unacceptable design flaw in this price segment (http://www.naturalnews.com/048903_Ultimaker_2_3D_printer_review_print_problems.html) and a lot of owners consider the feeder to be a serious problem that needs fixing.
I don't know if Ultimaker has made any design changes over de past 2 years on the current UM2 models but 2 years seems a long time not to come up with a solution for some of these problems (or do a recall on some of the parts).
As a newbie, it is very hard to get a feeling on how serious these issues really are and how frequently you have to deal with them.
Thoughts anyone?