Personally I always skip the insurance anyway, if it was a $400 frame then so be it, it is not the end of the world if it gets broken which given the 100's of USPS shipments I've had, all undamaged, seems unlikey.
If I was buying something for $1000+ then I accept it is going to cost a lot to insure that but the cost ratio is usually more palatable.
I pretty much always give the seller a disclaimer stating I'm forefeiting insurance.
From my end, USPS seem to work really really well, much better than our Royal Mail where the only way to guarantee they won't break it is to use the Special Delivery option, which is roughly the same as your Express.
If I was buying something for $1000+ then I accept it is going to cost a lot to insure that but the cost ratio is usually more palatable.
I pretty much always give the seller a disclaimer stating I'm forefeiting insurance.
From my end, USPS seem to work really really well, much better than our Royal Mail where the only way to guarantee they won't break it is to use the Special Delivery option, which is roughly the same as your Express.