I can't really comment on the pipes as I have used neither of them.
The underseat, and undertank, K&N will .not give you much benefit as far as flow goes. Triple K&N filters, or triple UniFilters, or a RamAir system will give you the best result. Any of those options will also make maintenance a LOT easier because you will be able to access everything under the tank
I HIGHLY recommend getting TuneECU so you can flash the ECU whenever you want without having to bother (or pay) the dealer. You can also do a whole bunch of other maintenance and checks as well. In addition, I also recommend getting PCV/AT. If you then ask Hans0 nicely for maps for both the ECU and the PCV/AT I am sure that he will set you up well. That way you will never have to worry about changing pipes or filters again as your bike will automatically adjust itself when you do. Very much worth the investment, IMHO.