I have to admit, it everything is going fine, I wouldn't take it in, either.
I sent my Horizon 7700 in one time in 4 years, just because I hadn't sent it in yet, but it had some small things I wanted them to look at. However, my husband had it apart underneath and found lots of lint where a normal clean it out wouldn't work. But that was after i had sewn almost nonstop on it fo 2-3 years.
It is to their advantage to have scared customers.