Duramax and Amsoil are my go to oils.

 

I've been using Amsoil for more than ten years.

 

Pennzoil Full Syn (Engine)
Royal Purple Synchromesh (trans)

 

Pennzoil Synthetic 0W20 Ultra
Honda A01 filter.

 

WallyWorld Supertech Full Synthetic 0W20 (while under warranty) and a genuine Honda oil filter. I've been using Walmart Supertrech conventional oils in cars since my Acura Integra. I've had 8 cars and a total of 629400 miles driven with no engine-related issues - three of those cars were sold with 150000-275000 miles. Supertech is SAE SN+ rated just like the Branded oils. My OCI is about 3-6K conventional and 6-10K synthetic - except for the Mazda RX-8 that gets 2K OCI (engine sump oil is injected into the combustion chamber to lubricate the rotary apex seals).

 

Mobil 1 w/Mobil 1 oil filter. Like Jazu, I've never had engine issues. I've had a few cars that I drove into the ground, and they only fell apart AROUND the engine. No burning oil, no drop in MPG, nothing. Also like Jazu, I tend to change between 6k-10k. My Fit is the first car that tells me when I need an oil change, so we'll see how that goes.

Edit: Also, quite often Autozone has an oil and filter special that I can get Mobil 1 oil and filter for around $30 US.

 

I've been considering the Canadian Tire Formula 1 Full syn as well as the Wally World stuff.
Honestly, with the rebates and sales promos it's actually cheaper (for me at least) to run Penn Full Syn.

 

Mobil 1 Extended Performance 0w20
OEM filters

 

Whatever's least expensive and still 0W20 full synthetic- Costco or Mobil 1 from Costco. Can't imagine there's much difference to a small non-turbo engine that I'm not pushing too hard.

 

It's the small sump capacity combined with DI which can lead to issues in the long run.

 

And the brand of oil makes a difference how?

 

It doesn't. Just needs to be monitored and changed more frequently...IMHO

 

Why? Has anybody shown any relevant difference between fancy and generic synthetic oil?

 

No brand specific but switched to full synthetic on initial change. Most of the time it has been Mobile 1 but have used Pennzoil and Castrol. Switched to Kirkland brand full synthetic recently. Always used OEM filter. Have done this with all my Honda/Acura dating back 2001. I did experience oil leak at the valve gasket but was after dealer did the VTC update.

 

Mobil 1 was what I used while changing the oil last month.