Typical of most BITOG posts, this question is not well defined.
So much more info would be needed to give a good answer. But I'll play along and give some "what if ...." scenarios.
Above all things, I'd have to question what state of "cleanliness" the equipment was starting out with, in the first place.
A reasonably clean engine probably would not greatly benefit from PU or FU, because there likely isn't much to "clean" anyway.
A filthy engine would benefit from much shorter OCIs and the tightest filter you can reasonably get. I would think PYB and TG would make a good combo.
And, conceptually, the holding capacity is likely going to be of major concern; but it needs to be "matched" with the intended OCI.
Most certainly, not all of the "cleaning" is going to happen at levels where filtration is effective. Much of it would happen in smaller um ranges where the oil would be expected to hold the particulate in suspension because the filter (even a good one) is too loose to catch all of it. I'm not convinced (although I would admit isn't not a horrid idea) that the use of a premium filter would be a total necessity. In this circumstance, an OCI is going to likely be more effective than any premium filter. So while I see the benefit of having a decent filter, let's not pretend like the filter (any filter) is going to catch all the stuff that the miraculous cleaning lube breaks out. A lot of it will stay small and float around until the OCI.
I would run a P-classic with no problems whatsoever, if the OCI was 3-5k miles, even with a "dirty" engine using PU. As the media loaded up, it would become more efficient, and still likely would hold out for 5k miles. However, to get any decent ROI from using the PU, I'd likley extend the OCI and perhaps use the FU filter due to it's higher capacity. But that drives up the cost further, and therefore moves the ROI.
And before anyone whines about me mentioning ROI for the bazillionth time, it does matter. Why waste a product, even a top-tier product? Cleaning and fiscal efficiency do not have to be mutally exclusive you know! They can coincide, but only if you plan and think your way through this. If one is going to "feel" their way through with emotion and not logic, then all bets are off.
Think of it this way:
Would you run the premium combo of PU/FU for 1k mile OCIs, for the entire life of the vehicle? Probably not. At some point, even the zealous BITOG mind realizes waste exists at some point. So the real question becomes "at what point"? Ah-Ha! There is a sane point of fiscal responsiblity that even the AR BITOGer would agree exists! One just has to find it. Don't "feel" your way into this blindly; think your way out logically!
So conceptually, if you are going to stick with short OCIs, I would suggest perhaps PYB, and the filter probably does not need to be a high-end filter, because depth media isn't going to matter much as you'll not be loading it for as long. I'd perhaps use the TG because of it's tight media. It does not have as much holding capacity, but the moderate OCI does not demand it.
OTOH - if you're going to extend your OCIs, then PU/FU would be a good choice, but you're really going to have to study it to be successful so that you clean well and still get some ROI.
