I am not a fan of Nikon and don't any of their scopes now, but 7-8 years back I had 5 Monarchs in different powers. I bought one new off of eBay and mounted it myself. This was one of the first scopes I mounted myself and was really heavy handed. So much so that I torqued down the rings and cracked a lens inside the scope. Yep, too much torqua along with a ring too close to the end of the tube and - CRACK. Anyway, I send it to Nikon, tell them exactly what happened and they told me to send it in. I got it back a couple of weeks later, fixed free of charge and they even replaced the tube I had dented.
Like I said, I don't own any of their stuff now but cannot complain about the service I got.