It has been perfect for me (FTPD), and any amount of research would show you just put in your switches ip in it instead of 0.0.0.0:5000 unless you dont search for problems.
Like searching was something that the kind of people who whould need this guide would do.....
And for personal experience for me ftpd on switch has:
corrupted my SD card 1 time
corrupted files transfered many times
lots of crash on switch
transfered files that are 0kb
transfered files that only appear when using ftpd
and lots of problems
etc
Is very unstable, if it has not done problems for you, then you are lucky, but ftpd for switch is not polished enought for be in a noob-ish kind of guide