I haven't gotten around to posting these individually, but here are 60,000 miles worth of UOAs on my 2016 WRX. Here are some key points:
-A couple of the samples were sent to both Blackstone (BSL) and Oil Analyzers Inc (OAI) for analysis.
-Subaru OEM oil filter on each interval
-Ran the factory fill for 6k mi, then ran Mobil 1 ESP 5w30 from 6k to 42k mi. Then I ran Rotella T6 Multi-Vehicle 5w30 from 42k to 60k mi.
-Car is bone stock engine-wise. Stock tune, factory air filter, etc.
-Commute is roughly 25 miles each day with some highway, some stop and go traffic. Generally pretty easy driving, not going into boost much.
-Roughly 20,000 mi per year on the car which is about 3 oil changes per year (OEM recommended interval is 6,000 miles)
-Road trips are taken a couple times a year in this car.
-Cold start idling in the morning is usually less than 30 seconds.
-Colorado climate, so it sees hot and cold temperatures.
-Every oil change interval (except factory fill) has at least a couple autocross events on it; usually do about 10 events per year with a co-driver.
-Air filter is changed at OEM recommended interval (30,000 mi)
-I believe the factory fill is Idemitsu 5w30, but I'm not 100% sure.
-Subaru specifies GF-5 or API SN 5w30 in the owner's manual. I wanted a more robust oil than a GF-5 oil, but I wanted to use a "5w30" API SN (although not RC) oil so I used the M1 ESP. When RT6 MV 5w30 was released, I went with that since it's cheaper. At 60k mi, I switched to Castrol 0w40 since the powertrain warranty is up. The Subaru UK owner's manual for the FA20DIT Levorg specifies 5w40 as an oil option in addition to 5w30 (I believe), so I went with it here.
Pretty happy with the car so far. There was a strange copper spike on the 42k sample. I'm not an expert at analyzing these UOAs, but I'm happy with the viscosity considering fuel dilution and potential shearing and I'm happy with the wear metals. Excited to see how the 0w40 compares. I was debating M1 0w40 vs Castrol, and I went with the Castrol with its lower calcium. However, the M1 0w40 is closer in viscosity to the 5w30s I've been running.
Code
Lab OAI BSL OAI BSL BSL OAI OAI OAI OAI BSL OAI BSL OAI
Oil Brand Idemitsu Mobil 1 Mobil 1 Mobil 1 Mobil 1 Mobil 1 Mobil 1 Mobil 1 Mobil 1 Shell Shell Shell Shell
Oil Model Factory Fill ESP Formula ESP Formula ESP Formula ESP Formula ESP Formula ESP Formula ESP Formula ESP Formula Rotella T6 Multi Vehicle Rotella T6 Multi Vehicle Rotella T6 Multi Vehicle Rotella T6 Multi Vehicle
Oil Grade 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30 5w30
Sample Date 03/05/2016 06/13/2016 06/13/2016 09/09/2016 01/29/2017 01/29/2017 04/23/2017 08/18/2017 01/26/2018 06/08/2018 06/08/2018 09/12/2018 03/09/2019
Drain Interval 5,918 6,255 6,255 5,770 6,004 6,004 6,080 5,824 6,062 6,231 6,230 5,977 6,492
Unit Mileage 5,918 12,173 12,173 17,943 23,947 23,947 30,027 35,851 41,913 48,144 48,144 54,121 60,614
Aluminum 5 6 5 5 5 3 3 3 4 5 4 4 3
Antimony 0 - 0 - - 0 0 0 0 - 1 - 0
Barium 5 2 1 0 0 0 0 0 0 0 0 0 0
Boron 175 138 143 148 148 136 191 130 156 108 112 85 98
Cadmium 0 - 0 - - 0 0 0 0 - 0 - 0
Calcium 1830 1123 1159 1102 1102 1044 1306 1003 1090 1105 1192 1177 1401
Chromium 1 1 0 0 0 0 0 0 0 0 0 0 0
Copper 128 66 71 19 6 5 3 1 21 7 7 2 8
Iron 36 29 29 19 17 15 17 15 26 15 15 10 16
Lead 0 0 0 0 1 0 0 0 1 0 0 0 0
Lithium 0 - 0 - - 0 0 0 0 - 0 - 0
Magnesium 11 6 0 9 9 2 8 5 9 562 623 700 614
Manganese 19 4 3 1 1 0 0 0 2 1 1 1 0
Molybdenum 680 160 166 95 92 83 104 84 90 17 18 5 2
Nickel 1 0 1 0 0 0 0 0 0 0 0 0 0
Phosphorus 672 630 653 723 723 703 824 639 702 661 700 674 717
Potassium 1 0 3 3 3 2 3 2 2 2 0 2 1
Silicon 263 62 60 21 21 19 24 19 20 25 26 22 18
Silver 0 0 0 0 0 0 0 0 0 0 0 0 0
Sodium 7 4 3 4 4 2 3 1 1 6 4 6 4
Tin 2 4 0 0 0 0 0 0 0 0 0 0 0
Titanium 0 0 0 0 0 0 0 0 0 1 0 1 0
Vanadium 0 - 0 - - 0 0 0 0 - 0 - 0
Zinc 766 791 791 841 841 821 974 808 880 736 782 769 855
cSt Vicosity at 100 C 7.8 10.89 11 11.14 11.03 11 10.9 11.3 11.2 11.78 12 11.38 12.3
Flahspoint in F - 410 - 440 445 - - - - 430 - 405 -
Fuel dilution (GC) 0.027 - - - - - - - 0.015 - 0.015 - 0.02
Soot 0 - 0 - - 0 0 0 0.001 - 0 - 0
Water 0 - 0 - - 0 0 0 0 - 0 - 0
Insolubles - 0.2 - 0 0.1 - - - - 0.2 - 0.1 -
TBN 3.88 2.1 2.61 3.1 1.8 2.74 2.66 1.74 1.75 2.4 3.2 4 2.27
TAN - 3.3 - 3.3 3.6 - - - - 4 - 3.7 -
Oxidation (abs/cm) 18 - 31 - - 34 30 33 33 - 20 - 16
Nitration (abs/0.1 mm) 10 - 9 - - 10 9 9 9 - 11 - 11
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...Probably wasn't worth it.
Regarding good looking UOAs, bluesubie mentioned once upon a time, that despite his Turbo Forester UOA results looking good, it didn't prevent his turbo from failing anyway; so there are issues that could develop and be outside the scope of what a UOA can tell you. Besides, the price of a UOA costs as much as an oil change itself so I'll probably only be doing them every other oil change now.
I recall some time ago (I believe here on bitog) someone posted a link to a guy that successfully removed a good bit of intake valve deposits by driving a Golf GTI (or R) on the track at high load for a while. He posted before and after pics as well. The results were not quite as good as walnut shell blasting, but you could definitely see an improvement. I've looked for the link again several times over the years but never found it again. Maybe I'll give it another shot.
FWIW, I do believe a lot of Subaru intake valve deposit issues are blown out of proportion a bit. While there have been some IVD buildup pics floating around the web there have actually been very little driveability issues (CEL's). Most of the Subaru issues are treated as preventative maintenance and reported power improvement verified via butt dyno's (with 
