This was brought up in the 50 gun theft thread, but I wanted to start a separate discussion on firearms insurance. As Cha Lee perfectly said in the other thread, "Everyone here needs to ask themselves honestly if their insurance coverage would fully cover their belongings if their house burned to the ground and it was a total loss scenario. If its not identified, appraised and documented the insurance company can easily tell you to stick it when a total loss event happens."
That being said, for those that have a supplemental policy, or have taken steps with an existing policy, what companies have you used? Did you have to give a list/values for the insured items with SNs? I know some carriers advertise coverage without requiring SNs--and I suppose it's on you to validate and document the value of your items.
Any recommendations? Pros? Cons? Headaches you've encountered?