As for more information in the post that I couldn't get through, you can search for
HKS G310 to pull up the information from Total in terms of Kia/Hyundai factory fill. If it was available here, I'd just use that. In terms of choosing the right range of oil, as stated, for most climates 5w-30 is best for the V6, and 0w-30 for the 2.0L. For those in very very hot climates, where it doesn't get cold, such as certain parts of the Middle East, 20w-50 makes sense. If I lived in Arizona, I'd use 5w-40 on the V6. For those in extremely cold climates, I'd make it easier on the turbos and go with a 0w rating. I live in Seattle, so 5w-30 is fine. If I was doing a summer road trip through Nevada, I'd put 5w-40 in. The shorter the temperature range, the better the mileage, so 5w-30 should yield better mileage than 5w-40. If you're going to be driving on a track for a couple hours, then 10w-60 makes sense--just be sure to change it after you're done.
I've actually not been able to find Total Quartz 9000 Energy 5w-30, in the US, nor the exact stuff, the
HKS G310. They do have the Energy 5w-40 on Amazon, which also meets Kia spec, but the 5w-30 should provide better gas mileage (on the V6, or 0W-30 on the 2.0L). The INEO Long Life, which is Total's latest tech, and has some elements designed for the strictest diesel standards, is perhaps the best Total option that's readily available here for US V6'ers. Amazon has three 5qt jugs for $127, so $15 more per 5qts than Mobil 1 at Walmart. Assuming you get a 3% benefit in fuel efficiency (vs Mobil 1), that should pay dividends over 6,000 miles. I'm probably going to use INEO Long Life for my first oil change, as I can't find 9000 Energy 5w-30. I'm currently getting 26.5mpg. My driving settings are "custom" with all set to "comfort" except steering, which is set to "sport" and I've of course disabled the fake engine noise. Gas is Costco 92 (Washington).
Mobil 1 is previous generation tech, and was factory standard for most high performance cars from the 2000's. Total Quartz 9000 and INEO are the latest tech, and are now the factory standard for BMW, Mercedes and Kia/Hyundai (among others). Mobil makes new tech oil now too (3000 XE), but it's not readily available in the US. Ravenol VMO is also a new tech oil, but only available in 5w-40, and more expensive than Quartz Energy 5w-40. Like I said in my original post, using current Mobil 1 is okay, it's just not as efficient as the latest Quartz line. For my previous car (Saab) I used Mobil 1 0w-40, which was the recommended oil for Saab's and all the German cars back then. Tech has improved in the past 20 years, and so have manufacturers recommendations. Kia is not randomly recommending Total, nor are all the other manufacturers. Their MPG claims are based on the oil used. The math is simple, you'll come out way ahead spending a little extra on the oil if you spend 3% less on fuel over 6,000 miles. Better engine protection is a bonus. My only issue is availability. I like that Mobil 1 is available everywhere, not to mention cheaper. When Mobil's new tech becomes commonplace, then we'll have the best of both worlds in the US (great quality oil available everywhere). For now, Quartz via an online retailer seems to be a straightforward choice for US shoppers.