I have used both but are both brands good to use? for my porsches?
thanks.

 

And BECK/ARNLEY

 

Visually, it looks to me that Mahles are made better ( this is mostly BMW filters ) but I am sure there is little performance difference. I use either one I come across at part stores or online.

 

For warranty I'd use Porsche.

 

Mahle makes porsche's filter. Mann is also very good though. Both are about same quality.

 

Yup Mahle is the OEM supplier to Porsche. For warranty purposes they'd have to prove the filter caused the failure. Personally I use Mahle since that's what's sold most of the time on ebay in the oil change packages with the new crush rings for my Turbo.