Learned a few tricks from my FR-S in regards to intakes and tuning.
Intakes by themselves are noisemakers just like it is listed above. A lot of car manufacturers are making a lot better designed intakes (Like the FA20 intake on the BRZ\FR-S) so simply replacing the filter lets more air through. The only way to make use of the airflow is to tell the engine how much air/fuel to use with the intake installed. The intake I had was very well designed on my FR-S, maybe slightly better than stock, but nothing spectacular from a performance standpoint. You see big V8's get great power gains from these intakes, but these tiny engines that are 2.0L and below just don't need that much air unless turbo charged.
K&N branded intakes are usually safe, oiled or dry. I have never had an issue with the filter in Texas and I owned my FR-S for almost 3 years with an oiled filter installed. There's always trade offs when changing out parts.
The cheapest route to get more intake noise is to remove the resonators on the stock intake box. If you're going for looks, then you'll probably want the short ram intake. Personally, I like the Injen intakes that go down lower and further away from the heat, but I haven't seen if it truly makes a difference in intake temperatures or not.