I had a full flow oil filter conversion installed by Wessex workshops around 25 years ago. Since then I have always used a Mann W719/5 oil filter or equivalent (ie FRAM PH2870A) with no issues. I was thinking however that the bigger the filter that can be used, the more efficient it might be, as the flow rate per cm2 of filter will be reduced. I was hence wondering what type of filter others with a Wessex conversion are using ?