I know this was accepted just 2 days ago, but you can't even find a seller or buyer at 3 ref anymore (plus I added 1 of my own proof)

Selling for a key (3.66 ref):

http://www.tf2outpost.com/trade/8215219 (1 willing buyer)

http://www.tf2outpost.com/trade/8698148

Sold for a key (3.66 ref):

http://www.tf2outpost.com/trade/7029385

http://www.tf2outpost.com/trade/8699365 (my trade: http://i.imgur.com/UNA8azH.png Sold mine for 3.77 cuz he got no time to buy me a key)

Conclusion: 1 key should be a good flat price as of now like Stabby.

p.s.: the "own" counter got it all wrong, I don't have any left :S