Speed density is always the way to go with F/I, big cam(s) or when you pass the g/sec limitations of the PCM (pretty easy to do). Mass air flow sensors aren’t as picky about environmental changes, but they can be affected by dirt/dust/grime and become inaccurate over time.
Both are obviously useful in their own sense, in the case of the LS1 PCM it uses both redundantly and I tune both if it’s feasible.