She's on! very happy with my new FMF exhaust system.

should I be looking at getting a better air filter is the stock one up to scratch?

I have a K&N air filter on mine with the same exhaust.
I have also done the "Ultimate Airbox Mod"....

I have a stock air filter and a gytr air filter.
The bike has a little bit more power with the better flowing gytr filter.

Since I ride off road I wont run K@N filters, they're fine for super motos and cars tho, theres not much dust on paved roads.