bear in mind - going stage 1 or 2 gets rid of the brutally lean stock tune that Subaru put on every turbo EJ since 2007. that alone would likely prevent most of the ringland issues we hear about.
if everyone replaced their oil pickups with the killerB unit early on, as well as put a proper (safe) aftermarket tune on their cars, I'd wager that horror stories would be rare.
when it comes to catch cans/AOSs, I'm one of the people who has had issues with theirs in cold weather. I've had my car freeze up twice up with a Crawford V2 installed, both during extended highway commuting in ~-30c. the lower drain line (on cars with TMICs) is long, and nearly horizontal, so it doesn't drain quickly. the line runs close to the firewall, in the line of fire of the hood scoop, which strips heat from the line when it's super cold. condensed water can only slowly drain at the best of times, allowing it progressively cool, freeze and sometimes plug, pulling oil through the intake and creating an epic James Bond smokescreen. good times.
I never had issues in stop and go city driving in >-25c. lower speeds and idling at lights likely helps thaw that line, and taking corners would likely help clear that drain line.
most people here don't have issues, but Calgary doesn't see much of a winter compared to the rest of the prairies. my car doesn't see winter anymore, so I left my Crawford AOS on. having checked numerous times, it does a fantastic job of keeping oil out of the intake/TMIC, which helps reduce detonation. if I had to do it all again I'd probably buy another one, but would revert back to stock for winter.