1.66 flat is what there's needed now, since 1.88 didn't sell.

Selling:

1.66 ref:

http://www.tf2outpost.com/trade/9573058 - Under 1 day old, no offers

http://www.tf2outpost.com/trade/9192257 - 2 weeks old, looks edited, no offers

http://www.tf2outpost.com/trade/9574172 - Under 1 day old, no offers - Same guy tried to sell it at 1.88 ref, no luck - http://www.tf2outpost.com/trade/9378306

http://www.tf2outpost.com/trade/9572983 - Under 1 day old, never bumped, no offers

http://www.tf2outpost.com/trade/9560026 - 1 day old, not bumped in a while, no offers

http://www.tf2outpost.com/trade/9561365 - 1 day old, never bumped, no offers

http://www.tf2outpost.com/trade/9553050 - 1 day old, never bumped, no offers

Conlusion:

Very easy to get at 1.66 ref, so 1.88 isn't needed anymore

Thanks for reading, feel free to tell me what you think and vote, have a nice one.