A cat ir0750 or equivalent just looks like it would last a long time even at 2 microns. The stock filter would be staying clean. My reality problem is where to put an additional filter of that size. The left headlight area would even be difficult. The thing is, I filled up with B99 so that got me thinking about finer filtration. Since then, I've been topping off with dino. Probably B50 now- but the exhaust still smells like BBQ.