I use Castrol - Edge 5W-30 LL. It took some time to locate other than the dealer but I have always believed in oil is cheap insurance. I work in an engine shop and see daily what extended oils services causes and the damage is not reversible and it escalates quickly.
I hate the factory skid and water pump location as well as the fact that the filter is only accessible from below. I can service the truck and Jeep in the time it takes to do the Jetta.
I need to find a good aluminum full skid to aid in this and the plastic leaves little for protection of the oil pan.
Not looking to start a full on debate (they've been well chronicled already) but vw507 oil has extended intervals due to the inherent metallurgy present in that oil formulation. From my understanding, there are a few stages. 1) scrub off old deposits of wear metals, 2) bed down new layer of wear metals (basically zinc) on friction surfaces, 3) normal oil operation window.
507 oils are a 10k mile interval for a reason. They were decreased to absolute minimum from Europe to deal with the American market mentality. If you short change the interval, you're likely (inadvertently) doing more harm than good to the cam lobes, rod bearings, etc. As in, change during the scrubbing window, when no there's no protective film bedded down, and there's more metal on metal contact than you'd think.
I have been doing used oil analysis for the last few changes and have noticed a demonstrable decrease in "wear metals" with increasing intervals, which speaks to the phase changes mentioned above. I'm over the 10k miles now and still going upwards.
Food for thought.