k&n airfilters
 

is the k&n airfilter part #B1000-145379, a reusable (clean able) airfilter?

Do a search here on K & N and see what other members think of them. I remember a post that talks about those things fouling the MAS on MBs. Might not be worth it.

MB air filters are overengineered in the first place. There's plenty of airflow, and no need to "improve" on something that already works quite well.

To answer the question, I belive all K&N air filters are washable and re-oilable. That being said, there is some debate about any peformance claims verus the price of the filter. One way to look at it . . . would you rather wear a pair of underwear for a year, wash it, and then wear it again, or would you rather just spring for a new pair?

I used K&N's on dirt bikes because it was more affordable to wash them out every other weekend instead of having a case of filters. So, it could depend on the operating environment of your car and the willingness to wash and carefully oil the filter.

I know for a fact that many people wash and rewear underwear. But of course most people are not equipped with an expensive mass air flow sensor that is ruined by doing so.

Yes.
P.S. Been using them for 25 years on All of my vehicles & have never ruined anything.

You have to be very careful when cleaning them, and that is why I stay away from them. I've seen several Ford PSDs that had dirty intakes because the filter either did not seal very well, or allowed dust through.
IMO, not work the risk, especially considering the cost and claimed performance gain.