So, I'm under the impression that a heat shield is a must when using an induction kit, or open cone filter. My reasoning behind this is with how not it is under the bonnet, without a shield all that hot air is going to surround the filter. Meaning the filter will suck in hot air, a heat shield around the filter with help stop, not completely stop but help stop the hot air being around the filter which means it won't suck in the hot air, and rather more suck in the cold air from the cold air feed (if you have one) however, a mate is a adimant that you don't require one. Would love to hear your thoughts on it anyway.

Cheers

The radiator fan does blow directly into that area so I would recommend installing one. Another thing no one seems to mention is that they also help keep water away which is definitely important.

Depends if you want noise or performance. For noise keep it open; for performance you want as enclosed a system as possible, feeding in ambient rather than engine heated air. Minor mods to the air box (such as the Mountine and ST200 have) plus the "free" intake mod have decreased my intake temperature considerably.