Thank you! I actually bought it new, but used those free oil changes until they ran out. Certainly considering going every 5K (change no later than that) since I put on roughly 25K a year 🤮 I try to squeeze 8 years on every vehicle and that way, it boils downs to about .20 a mile which is very acceptable.. especially since by the time I sell it, I still get a nice $5-6K for the vehicle at least.
Very good. You'll find that Quaker State Full Synthetic (QSFS) 5W-30 has a higher kinematic viscosity @ 100 deg C (KV100) as compared to most other 5W-30 oils. And, it has a strong add pack.
I cannot think of a bad UOA with this oil as well. Though, please don't extend OCI's with it -- it wasn't designed for that.
Here in Alaska, I've settled on either this QSFS 5W-30 or Costco's Kirkland 5W-30. The settled deciding factors were price, GM's D1G2 cert, and their known winter and summer performances in my stable of GM vehicles -- to include BITOG UOA's and general recommendations of folks I trust here.
I've occasionally used both Mobil and Castrol 0W-40 oils. But they cost more today, and I don't believe they'll gain me anything into the future.
The key to most every ICE vehicle on the road today is timely maintenance. Do this and you're miles ahead of most out there.