First, and interesting discussion. Secondly, I can say with certainty that I'm not opening up mine both because mine is perfect and because I would not attempt want to void the warranty if it was broken.
I happen to think it is a superb loco in every way - just very impressed with how smoothly it runs and how great the sound is. I don't have much use for the cylinder steam effect, but then I suspected that would be the case when I ordered it. But I love the Force Coupler. What a great idea!.
I have a seven other Vision locos and I think this is the best one yet.