I've used those feet on my bandsaw and milling machine and they work well for levelling. Lathes can be a bit fussier, though. How stiff is the cabinet - would it be happier supported at 6 points rather than 4? Will the cabinet itself distort? How many mounting points did the manufacturer provide? I would be inclined to go for 4 as that makes the levelling and calibration easier. Not that I can talk - my lathe sits on thin MDF and ply packing...