Air intake systems in order of performance (on the road)
1. Pressurised air box
2. Ambient air temp fed High flow filters (Apexi, Greddy, HKS, etc with cold air feed)
3. Engine bay mounted High flow filters
Where option 1 is way above option 2 and 3.
However, when High flow pod filter manufacturers quote bhp gains, they use a dyno, i.e static air conditions, where a pressurised system is not being fed enough air to buid pressure.
From the above, we can see that one of the the best systems would be to use a standard airbox, and fit a pressurised snorkel to feed it.
The stock unit already has such a snorkel, but it is not the best design. Unfortunately the stock airbox is kind of upside down too, as in the filter is on top, so it leaves little room to make up a good snorkel system.
But implemented correctly, this system would offer better performance than even if you were to run no filters on the MAFS at all.