The writing has been on the wall as far as Royal Purple filters, thus why many of us bought twenty or thirty years worth. At a minimum I wouldn't trust buying anything more than one filter from them, and cut it open. I haven't seen something that says they are completely garbage yet, but from recent experiences I'd say they went from an a+ to a b- until and if we get more verification.
SRT sounds like a great option, bottom line spun microglass is the way to go, so another thing that will beneficial to the forum is if guys start cutting open SRT filters like we have done with RP filters to make sure the media is holding up with extended miles. Maybe knock RP of it's perch, but I need to actually see and hear a few experiences before saying that personally.
