5 keys is a quicksell price now. Yes, I have 4, but I've also got a proof. See it below. Market is flooded by quickbuyers at 5 keys, a lot of people offers 6 - 6.5 keys (even 7). I thought about 6-6.5 keys range, but some trades are still happens at 5.5 and too much unsold for 6 keys to make it the low-end.

Sold / Bought:

http://www.tf2outpost.com/trade/14164053 - bought for 7 keys

http://www.tf2outpost.com/trade/14275352 - sold for 7 keys

http://www.tf2outpost.com/trade/14291607 - sold for 6.5 keys

http://www.tf2outpost.com/trade/14285695 - sold for white bill's (6.5 keys)

http://www.tf2outpost.com/trade/14259573 - sold for 6 keys

http://www.tf2outpost.com/trade/14313357 - sold for 6 keys

http://www.tf2outpost.com/trade/14217482 - bought for 6 keys

http://www.tf2outpost.com/trade/14134082 - bought for 5.5 keys

http://www.tf2outpost.com/trade/14330253 - sold for 5.5 keys

Offers:

http://www.tf2outpost.com/trade/14195001 - 5 keys, 5.3 keys, bill's (6 keys)

http://www.tf2outpost.com/trade/14242479 - 5 keys, 6 keys

http://www.tf2outpost.com/trade/14257835 - 5.3 keys, bill's (6 keys), white bill's (6.5 keys), strange Huntsman (6 keys), strange Disciplinary Action + 1 key (7-7.5 keys)

http://www.tf2outpost.com/trade/14297051 - "6 keys + some ref"

http://www.tf2outpost.com/trade/14049023 - 6 keys, 6.3 keys

Sellers:

http://i.imgur.com/7TC5GQf.png - classfields: 5 keys + 5 ref, a lot of 6 keys

http://www.tf2outpost.com/trade/14333024 - 6 keys

http://www.tf2outpost.com/trade/14338880 - 6 keys

http://www.tf2outpost.com/trade/14335363 - 6 keys

http://www.tf2outpost.com/trade/14297678 - 6 keys, 2 willing buyers

http://www.tf2outpost.com/trade/11015306 - selling for Bill's, got a lot of adds, probably inactive trader

http://www.tf2outpost.com/trade/14341631 - 6.5 keys

http://www.tf2outpost.com/trade/14348529 - 6 keys + 5 ref

Buyers:

http://tf2tp.com/trade.php?trade=9777227 - 6 keys, fresh trade

Quickbuyes (listed here just to show that 5 keys is a quicksell price):

http://www.tf2outpost.com/trade/14156525 - 5 keys

http://www.tf2outpost.com/trade/13865083 - 5 keys

http://www.tf2outpost.com/trade/14351174 - 5 keys

http://www.tf2outpost.com/trade/13957520 - 5 keys

http://www.tf2outpost.com/trade/14233762 - 5 keys

http://www.tf2outpost.com/trade/13545557 - 5 keys

http://www.tf2outpost.com/trade/14347976 - 5 keys

http://www.tf2outpost.com/trade/14250475 - 5 keys

http://www.tf2outpost.com/trade/14290373 - 5 keys (probably not a quickbuyer, anyway no success in 3 days)

P.S. trade.tf shows 5.8 keys - http://i.imgur.com/5xuMCNS.png