The "should" recommendation seems like the right direction, but feels like it needs an explanation (in case someone's trying to run some 2.7 code and is wondering why their comparisons don't work anymore). Unfortunately, it's a little complicated to pile into a section like this. Putting it somewhere else (that includes a reference to -b) might work.

A somewhat related aside is that I've sometimes thought that there ought to be something a little more extensive regarding converting bytes to strings, as it's the kind of thing that can lead you down this road anyway.