So, on my GM 3.6 I usually run the ACDelco PF63e. But on a recent "trip" to RA, I spent a few extra bucks and bought a Wix 10255. Both have the correct bypass valve pressure setting but Wix boasted a lower micron rating for a high flow filter. I'm posting pics of both. I don't understand this--I am buying the Wix because I am worried about micron sized contaminants and there are shards in the filter. The oily substance on my finger is from the inside of the filter, you know the part where the "Clean" oil is supposed to come out (pic 2). I didn't post the results from the AC Delco but there was just oil. No more.