You won't get any gains in terms of power, but you might get a gain in fuel efficiency and a Shiite load of noise (assuming you get a pod filter). As Daryl said, the reusable filter will pay off the kit. In the event you can't find a kit for the 2az-fe, you can probably land one from the US or simply keep the airbox and throw in a panel filter. With regards to the RSB, in terms of handling getting a bigger RSB (I have the 20mm Whiteline, blade adjustable model) will give you the best value for money handling mod you can get. I highly recommend it. Modding the Gen5 is a little tricky given how few items are available for it.