Drop-down pin plus safety cable is the ticket. I use a baby Matthews drop-down on my Avenger D650 (which could also take a massive junior drop-down). Anyway, hanging a 20-lb load upside-down is no problem at all. Profoto fixtures and heads provide all-aspect head adjustment: if yours are lacking that feature, select the swivelling version of drop-down.

Do you add the swivel onto the drop down pin, or is there a drop down pin with a swivel built in?

This f830 looked interesting, though it'd be a bit more weight on the end:

http://images.avenger-grip.com/imageservlet/image?sysid=125449678889098077&format=avenger_html_product_detail

The drop down has a swivel built in.

erichard wrote:
Do you add the swivel onto the drop down pin, or is there a drop down pin with a swivel built in?

This f830 looked interesting, though it'd be a bit more weight on the end:

http://images.avenger-grip.com/imageservlet/image?sysid=125449678889098077&format=avenger_html_product_detail

The F830 affords a more limited range of motion than the E700 drop down pin. These two photos demonstrate the maximum upward deflection of a boom arm that still permits the baby pin attached to an F830 and E700 to remain perfectly vertical:

F830:



E700:



In the case of the F830, if the boom arm is raised further, the baby pin will deflect:

thanks again everyone for all the info. I have the E700 on order.

Got the E700. Works great but...

It lowers the effective max height of my boom and because of the limited ceiling height in our studio, it's not going to work for many of our shots.

I ended up filing the edge flat on my D600 boom stud it seems like that's the best solution for me.