IMO, a well made extended OCI filter with a very solid efficiency rating, 99%>20um. Been a few post use STP XL anecdotes that have looked good. That said, with a regular price greater than the Ultra and an off shore coo, wouldn't be my first choice in that tier filter.
However, if part of a solid AZ oil/filter promo, I'd use it. Just haven't seen anything that beats WM oil and separate filter of choice purchase. But as pointed out occasionally some don't prefer to shop WM.