I've been using one of the newer style Purflux oil filters on my 300 SEL for the past 1800 miles and it seems to be doing a great job - the oil has changed color.
This alone shows me it is doing well considering the stuff that came out of there looked like
- it was as black as the Hengst oil filter that was on the car and the filter had a date/mileage written on it that was basically 2 years & 17,000 miles
(previous owner not me!)
Anyway, this new Purflux looks to have some really decent filter media in it as seen in Gilly's photo:
http://www.peachparts.com/shopforum/attachments/tech-help/4053-w124-new-replacement-oil-filter-smaller-better-mvc-028f.jpg
The Delorean owners love them:
http://www.dmcnews.com/Techsection/oil_filters.htm
The MFG's site:
http://www.filtrauto.com/epurfl.html
&
http://www.purflux.com/e_0411__.html
It doesn't look to be any cheapo, that curve pleat design w/ metal endcaps looks pretty nice.