going back to your original post and problem statement, i cant see why the map sensor would be better at light load tuning
if anything, the airflow meters would be better as they measure actual airflow over the hotwire vs the map sensor that guesses load based on pressure (pressure != volume)
you need to remember if you go for twin Z32s these are 80mm each, whereas stock BCNR33/BNR32's are 65mm so you will get more airflow resistance on the std items, which translates to a more accurate airflow meter reading, which translates to a more accurate tune (more variance in the load cells).
if you go for twin Z32s then at 80mm each you might find it feel more dampened and sluggish as each intake is larger and it dampens the signal a little.
i would strongly think about what you are trying to solve before you do anything as you might find it worse
in my skyline i had the powerfc and i loved it and in my evo ive got the vipec and its pretty good also
the vipec is map sensor setup (previous owner changed setup) and it works pretty well but i can feel it is a little doughey on light cruise
i suspect thats due to the map sensor and large cams (270degs) and all the other crap done to the engine but either way, im not convinced map sensor "is better" for light load tuning
yeah sure the vipec has more features and is "this generation" but it doesnt have a simple hand controller which really sucks
but then yeah some of the other features are nice (launch, gear judge, logging etc) but it's a 20x20 ecu at the end of the day