Do the newer style 2 stage filters work better than the one before it?
Are you taking about coming from the single stage air filter that came with comes with all the 2.5 models? If so, yes, the new two stage air filters work much better, they let in quite a bit more air into the engine, and they stay cleaner longer.
I have 3.3 models with air filter housing that has a screen. I don't know if the screen makes it a two stage
you know.. i never had a sig.. but i do now...