Gadget Post Update
I went ahead and bought a dedicated vessel for the task and used it for my second go at a pair of steaks. I remembered to pat the steaks dry before searing them, and really cranked the heat on the cast iron skillet. My infrared thermometer was showing it at 600 degrees when I flopped them in. I could have gone higher but I was afraid I would burn the seasoning off.They came out some better than my first go, there is almost no grey along the edges of the cut and the sear is better developed.
A word on the the items as delivered: The expandable rack is too big for the size of the box, and the cut-out for the circulator was not as pictured. I have a bigger polycarbonate box the rack will work just fine in but I’ll be looking for something smaller for the one in the photo. The lid is not a problem.