I understand the difference with the warranties between US and grey market (5 vs 1 years, and Nikon service vs sending it back to the store). But realistically, what is the likelihood of needing warranty service? I take good care of my equipment, and as a non-professional, it doesn't see the kind of heavy use that might accelerate wear issues. In particular, I'm looking at the Nikkor AF 50mm f/1.4 and AF 85mm f/1.4D lenses. They price difference at B&H or Adorama for example is around $130. Given that, are the savings worth the risk?