To be very honest, I would probably wait another day or two and the sellers would probably be at 5 keys.

Also when dropping an item's price it's best if you provide item history (seller profiles are fine too but showing the item itself is better)

http://backpack.tf/item/644469021

http://backpack.tf/item/644048087

http://backpack.tf/item/637401310

http://backpack.tf/item/638530432

http://backpack.tf/item/637604769

http://forums.backpack.tf/index.php?/topic/36705-guide-for-non-unusual-suggestions/#entry559704

If you want some other tips and tricks on how to make a good suggestion, just read through this thread. It contains a lot of helpful information.

Sellers down to 5.25 and 5.2... should wait for them to mature.