I use K&N Air filters on all our vehicles, my Rocket the Customline ,The F100 and our Diesel Land Cruiser , we replaced the Donaldson twin air filter elements on the Mack prime mover with K&N elements all with good results, I didn't install the K&N filter on the Rocket for performance reasons rather because I do a lot of unsealed road riding and the rechargeable filter is a no brainer choice as the stock filters clog up quickly in dusty conditions ,I would not even consider pods, or after induction filter ducting when riding in dusty conditions I have seen the damage first hand from a slightly unsealed throttle body filter in fine red dust ,terminal scoring of the bores on a near new Yamaha FZR 1000 with badly sealed pod filters.
As usual Steve I take a long track to get to my destination, a lot of beating around the bush but, yes I prefer the stock induction plumbing on my Rocket just with a rechargeable Element
I was waiting for someone to tell me the FZR1000 was carburettor fed but the one I am talking about had a after market Fuel injection set up and for a short time was a very quick bike
The 2780 K&N's fit under the bearclaw but one does crush a bit. Attached pics of the OEM Air system and my first filter mod (changed now) marvel at Triumphs ability to kill noise and power. Ram Air think fits better and having the place to mount the ATP is a bonus. If you go K&N you also need to make sure the air temp sensor is in the airflow not sitting on top of the motor it will cause issues, trust me