This is the BIGGEST problem with eBay... They're feedback system is totally worthless! If you leave a valid negative feedback, you'll receive a retalitory negative feedback!

How many people should have negative feedback and don't because they threaten with a retalitory negative feedback... and likewise, how many have negative feedback that shouldn't because they gave someone a negative feedback that deserved it and then received a retalitory feedback?

So now it's your choice... do you accept his threat or do you do the right thing?