Run the best oil you want to spend money on in 5w30. Mobil1, Castrol, pezoil, royal purple, etc. I run Mobil, Castrol or penzoil full syn 5w30 and change it every 7500 miles. If you run conventional then to the 3k change intervals.
Find a reasonably priced 5w-30 Dexos oil. If the label has Dexos on it, then it meets the OEM requirements. It's kind of a scam from what I've learned about oil ratings, but it DOES mean that it has met certain criteria for that motor.
Or, like stated above, go with a known premium oil and stick with that. A lot of premium oils that don't say DEXOS APPROVED, meet the criteria or exceed the criteria for a 5w-30 synthetic.
I've personally used a good off brand made for fleet use by RELADYNE and it has been stellar for MANY oil changes. Plus it's reasonably priced because the sticker doesn't have any big name on it.
How do you guys feel about changing oil, but not the filter? I currently have a Fram Ultra Synthetic oil filter which I’ve read is one of the best you can buy and is designed to run up to 20k before changing (not that I’d ever run it that long).