I traded Miipo for this unusual with a DP Rotation Sensation (traded away).

The Fortunate son on his Outpost trade said he was specifically selling it for 50 keys, which is the only one selling on outpost, the other seller was apparently not willing to trade. (http://www.tf2outpost.com/trade/27850153 the trade.)

He did not mind about the bad third-gen effect on the Rotation Sensation, although it was an all-class hat. He liked this & accepted.

If you check on the unusual pricelist for Rotation Sensations, the Dead Presidents effect one is 50 keys, so essentially it marked the pure price & he accepted it as if it was pure.