In reply to bobpilgrem:
To help you get on with them a bit better than some seem to, I offer the following:
Pull the tab down before you ty and remove a screw. Empty flutes should therefore have the tab out of the slot. Make sure you click the tab back in when you place a screw in the flute.
I'm not keen on putting them on a sling as they can be tipped upside down, which doesn't help. As I intend to remain the right way up, I prefer fitting them to my harness. On my current harness they fit well on the gear loops (3 on one side, 2 on the other for Scotland, plus a 22cm screw on a clipper).
On a previous harness, a few minutes getting busy with some coathanger wire made a suitable fixing between the gear loops. I think Petzl harnesses have slots to suit, but I may be mistaken.