I gotta say, I was a bit skeptical, did the research but I kept surfing Ebay and last year, I got one for $60-70. So I broke my engine in and just changed the oil last year, didn't bother taking it apart, so I figure I have 3000 km's on the filter. I just took it apart while getting the head fixed and WOW, the crap on the filter surface was amazing, they really work. I had also had the rods out and there wasn't a mark/scratch on the bearings so I am convinced they work. Up to this point, I was considering switching back to a regular one but not anymore.
The only drawback is it takes a bit of time to clean it out but considering I usually change my oil 4 times a year, thats $60 in filters and I technically, this would be my 3rd one so thats $45 I've saved already,