I just found your post. I have had a 4800 for almost 20 years and it has been wonderful. I have had it serviced occasionally, but have had no trouble with it. The automatic needle threader was out of adjustment when it was brand new and I never used it, so I don't know whether it could have been adjusted. I love the machine. But unless I were getting it from a dealer, I would want to have it checked out by a dealer just like you would do a used car.
Peace and grace, FroggyinTexas
I am in the process of buying a used Janome Memory Craft 4800. Interested to know if anyone on here has one and any feedback.