Yeah no way to tell what the actual gains are, if any but I do feel a tiny tiny improvement, as I mentioned above.
Also per ARMAX/Safari:
"Our brand new performance orientated Safari Snorkel product line.
These snorkels are all new designs, tested on a custom built flow bench, to flow 25% to 70% more air than the stock air cleaner housing flows from the vehicle manufacturer, whilst still providing a watertight raised air intake.
This ensures that if the vehicle owner wishes to increase their vehicle’s engine performance (utilising Engine Management, Exhausts, upgraded Intercoolers etc.), the Safari ARMAX™ Snorkel will provide the necessary airflow required. This is the only product of its type in the world."
-certainly this is going to be much more true for a FI diesel as they imply in the paragraph above but the snorkel, according to Safari, should be adding airflow, which makes me wonder if URD could tune it with the Maf Cali to actually see a real (though minor with all air intakes, I'm sure) improvement.