I recently got a second hand 1D x. One of the first thing I did was to format the cf card that came with the camera. I also use one of my old cards from my 1D IV.
I use a card reader to import directly to LR. Recently pictures are on the LR import screen not in the order I took them but...
I normally shoot RAW (NEF) with Nikon D810 and use LR happily up to that point.
On a one off trip I wish to set camera to RAW+JPG Normal with a CF in the primary (RAW) slot as usual.
I will then put an SD card in the secondary slot (JPG)
While on trip I would transfer the JPG to...