I don't like the swinging gate from IIX. Here's why. The mounts only clamps
to ONE leg of the tower. You have to tighten the U bolts too tight to get
the mount not to turn. This puts way too much pressure onto the leg.
I like a design that I found here:
http://www.arraysolutions.com/Products/sidemountusersguide1.htm ; It Uses
angle iron to connect to two legs of the tower. There is no possibility of
slippage so you don't have to over tighten the U bolts.
Array solutions seems to be over engineered for most antennas, My homebrew one
is a compromise:
TowerTalk mailing list