I'm not to keen on giving out SN, any thoughts on this?
You aren't exactly "giving out" the serial numbers, you are giving that information as part of a contract with the insurance company. That's what a policy is, a contract. There are various legal rules that apply about the information, and I doubt it would be legal for the insurance company to give out your guns serial #s to anyone else.
ASK them. Gun, camera, watch, car, boat, anything that has a serial # (VIN #) etc. Who else can get that info?
If they don't know, or won't say, I suggest finding a different insurance carrier.
Up to you, of course.
Also, sometimes, you get stolen items back. If there's a record of you owning them by serial #. Some years ago, a friend had a rifle stolen, (all properly documented ser# etc), and his insurance paid him for it. Last year, the police recovered it. The insurance company (having paid him for it some years before) didn't want it, so the police gave it back to him.
(and the insurance company didn't ask him to return the money, either...)
That certainly doesn't always happen, but sometimes, it can...