Is the front the main airway into the engine compartment? Surely getting more air? Plus heat soak will be less due to being enclosed...
....Yes, the front is the main airway and does get the lion's share of the air. However, for what it's worth there is a surprising and somewhat illogical additional air input available from behind the headlight unit. Forge's Twintake exploits this and Forge found that testing with just a frontal single cannister filter, in their case, delivered less gains than with their twins.
I had quite a few phone conversations and emails with ITG's Andy (an extremely helpful and knowledgable guy) before their Maxogen was publicly launched but late in its development. I always hated the foam blocks but would have had to pay a lot of extra money to have what they have now modified (I would have wanted it in carbon).
ITG have a very well establshed good reputation for specialising in air filters and I know that VWR have been looking for a good 'technical partner' for an air intake for a very long time (years). So, ITG + VWR + APR = Thumbs up
and I doubtless would have considered one of theirs if it had been available before my Forge Twintake (which I might add I am extremely happy with).
What's amusing is that ITG were 'in bed with' APR's arch rival Revo previously. No matter, such is the motor industry and trade.