Exposure Automation: This turned out to be a major disappointment. It actually worked sporadically, and at first appeared to properly dispense the proper amount of light when needed. However, it eventually failed completely.
In short, the Exposure Automation was a complete bust.
Sensor Sensitivity: Both the Exposure Sensor and the S1/S2 Optical Remote Sensor face forward. The Lux Senior relies on light bouncing off of the subject to trigger the flash. It will work in a multiple flash, key and fill light setup when used indoors, but it is not sensitive enough to work outdoors. This pretty much limits the Lux's use to indoor venues if you're relying on the built-in S1 or S2 optical triggers. You could potentially add a more sensitive, hot shoe optical trigger like the Wein, but that's one more piece of equipment to carry.
In short, the S1 / S2 Optical Triggers work, but only marginally.
I really wanted to love this flash, but instead, will keep it because for a certain type of photograph, it can potentially do exactly what I wanted. Sure, the so-called exposure automation was a total disappointment, and the fact that it died after only a few hours of use is inexcusable. It will never ride along as my only flash unit since it's beam coverage is too narrow to be useful.
The sample photo was made with the Lux Senior placed about 3 feet from my face. It was in the S1 mode, and triggered by a second flash bounced off of the wall behind the camera. The lens was a Fuji kit lens zoomed out to 35mm and held at arm's length.
I won't be returning the flash because its dish reflector does have a place in my work flow. I see it being used outdoors for quick headshots during informal events. I imagine it being used during San Francisco's Carnaval, if and when it returns to its former glory. It is a target rich environment, one where everybody expects to be photographed, a situation where permission is implied. I will be using some form of compact radio flash trigger, and am quite sure I can consistently guess a flash to subject distance of 3 feet. Once this is all dialed in, I can be certain my exposures will accurate and easily corrected one viewed during Image Preview.
To close this series of posts, I can say that the flash does offer a fair compromise between a small softbox and a standard unmodified speedlight. It provides a soft edged, relatively narrow beam of light that matches the acceptance angle of a "normal" lens (50mm Full Frame, 35mm APS). When used manually, the output dial is easily rotated with only one hand.
I really wanted to love this flash. Alas...