IMHO the DrapeBoss is far superior to the Worthington Add-A-Motor. I tried both. While I was unable to get a chain that would work with my Hunter-Douglas wheel and the DrapeBoss, using a cord seems to work with very little slippage. (I adjust the blind about once every 6 months).

The problem with the AAM is that it is a toggle up/down, rather than discrete signals for open, close, half-open etc. This makes automatted operation while I am away risky. A power failure or other glitch and the AAM is opening the blinds at night and closing them in the morning!

I made some comments when I was installing/testing the two units, here they are:-

Butler Model 80 Add-a-Motor

Uses Appliance Module. One address. Toggles between two pre-set positions.

Noisy.
Friction pulley, not socketed for chain.
Open/Closed pre-set positions only.
Adjustable with remote between pre-set positions.
Impossible to know (in Xtension) where the blind is located.
Good mounting, plenty of adjustment.
Economical alternative, but does not satisfy my security needs - one glitch while I am away and the blind will be closing in the morning and opening at night!


DrapeBoss

Uses Power Line Interface. (One Powerline interface can serve mutiple DrapeBoss’s) Uses up to 8 addresses. Open, close, and up to 6 pre-set positions. (Older version uses 10, the last two, which allowed small steps, have been dropped on later models. This is good, because now you can only use as many as you need, and not have those last two way out yonder! Adjusting the blind 1/2” at a time was not convenient either.)

Quiet.
Chain pulley, but chain size not always compatable with blinds.
Open/Close and up to 6 other pre-set positions.
Not adjustable between pre-set positions with remote.
Always know (in Xtension) where the blind is located.
Poor mounting, inadequate adjustment.
Large unit.