I use Bombora triple action cleaner as that is able to run through the steam arm.
Note your option No 1, and possibly option 2, which i have not used, the manual says dont run through steam - others have done it and jammed the machine.
SB descaler will crack the scale off like plaque. Bombora triple action dissolves it.
So the relevant blurbs go. Im happy with the Bommy as it dissolves the rubbish.
Hope that helps