O.k. Let's see if I can clear up some things and tamp down some of the acrimony in this thread.
On costs:
I certainly didn't buy a WRX to squeeze every last quarter cent per mile of running cost out of it. I've got a Honda Civic for that, and even there I'm not wound that tight. My local Redline dealer cuts me a deal, so for me the cost difference to other high quality synthetics is substantially less than many here are supposing. The least value added expense in the whole process is the UOA itself, it costs much more than the difference between Redline and other quality oils. I do the UOAs primarily to satisfy my curiosity, it's a twisted kind of hobby. I rationalize the expense to myself by saying I might catch a real problem, like the high Si levels in my Civic.
On posting UOAs and their interpretation:
I share my UOAs primarily for the benefit of others, I do not need much if any help interpreting them. I also don't need a bunch of unsolicited advice on which oil I "should" be using. If I have specific questions I'll ask them in the first post. Comments and discussion are appreciated, but keep it civil and try not to project your priorities onto my choices or the choices of others. Many seem to think of UOA as an exercise in cost minimization, others think the primary benefit of synthetic oils is extended drain intervals. Neither assumptions are true for me. Extended drain intervals are only one reason to use synthetic oils, there are others and Redline fits into the "other" category.
On other oils being "better":
I've done a UOA on every OCI since the factory fill in this car, I've used GC and RT6 extensively and know exactly how the engine responds to them. Both perform very well, but I decided to experiment in order to satisfy my curiosity. RT6 is a bit thicker than optimal in Minnesota winters, and GC sometimes showed 15%+ shear and slightly low flashpoint in my application. Also, GC has been superseded by M1 0w40 as the preferred 0wXX HDEO, so my experimental choice was between the new SN formula of M1 0w40 and Redline.
When I decided to switch, the SN formula of M1 0w40 was still an unknown quantity and I was driving more, so the original plan was to go with Redline 5w30 for a ~6,000 mi OCI in the summer and Redline 0w30 for a similar length in the winter. It takes at least 3 OCIs of a new oil, especially one as atypical as Redline, to get good information, so I stuck with it and here we are. Knowing what I know today, I likely would have gone with M1 0w40, but at the time we didn't know if the SN formula of M1 0w40 would shear as badly as the old SM formula did (often thinner than GC!).
I see people recommending M1 0w40 as "better" for my cold weather than Redline 5w30. In very extreme cold this is true, but only to a small degree. At most temperatures Redline is actually the better choice, though the differences are always minimal.
Redline 5w30 has an MRV of 15,000 at -35*C and M1 0w40 is 31,000 at -40*C. Using the 5*C doubling rule, the oils are all but identical in pumpability. Mobil doesn't publish the CCS value for their 0w40, but it must be below 6,200 Cp at -35*C. Redline 5w30 is 6,000 at -30*C, so M1 holds the advantage in ease of starting at very cold temps. My car starts easily down to 0*F with RT6 in the sump, and I have both a block and a pan heater, so the ease of starting advantage of M1 0w40 is not that important to me. At temperatures above 0*C, the fact that Redline is a 10.6 cSt oil while M1 is a 13.5 cSt oil comes into play. M1 has a higher VI, but Redline is still thinner. Since even my winter OCI will include spring and fall temperatures of 15*C+, this is relevant.
In the end, the paper analysis indicates both oils are excellent and determining which one is better for a particular application would require a lot more UOA data than most are willing to collect. I decided to try Redline because of a lower tendency to reduce the octane of the intake charge, and it might offer some reduction in intake manifold deposits. These characteristics are owed to its low volatility, resistance to high temperatures, and additive package designed to preserve octane. My car sees occasional Autocross and track use and those characteristics have some value to me despite not showing up in a UOA.
Cheers-
