>The notion that negative feedback ought somehow only be posted in event of egregious misdescription is a bizarre, Ebay-centric one.

When you keep in mind the effect bad feedback has on a seller, you really should stay your hand unless you feel they were really out to screw you (or you're just plain vindictive).

It's a buck in shipping. I'd pay it, blast them an email asking WTF, maybe leave a neutral at worst. Bad feedback is reserved for fraud, IMHO.

Then again, the seller in this case appears to be a litigious asshat, so fire away.