Had it for almost a year now. Instructions on website were clear on how to measure. To begin with I wasn't sure if roller or concertina blinds would be more appropriate for us, but a couple of email later and the pros and cons of each (relevent for what we wanted to do) made the decision easy. Delivery was straightforward with robust packaging. As suggested we constructed and tested it flat on the floor, before installing it. No issues. The trickiest thing for us was getting the measurements correct to allow for the frame depth as we were mounting it diagonally - definitely a case of measure 16times, cut once! Overall I'm very happy and it's made a surprisingly big difference to the room.