Castrol's advertising actually puts me off their products.
I stick to brands like Mobil 1 and Fuchs for synthetics, and Motorcraft or Pennzoil for Group II/III based oils. When I was at the store last week, some guy came up and decided to 'lecture' me on motor oil. He was commenting on how the bottle of Fuchs Titan SuperSyn 5w30 I bought was an 'oil', and how Castrol was a 'lubricant' because it 'got to the top of the engine quicker'. I just wished him good luck on his GTX 20W-50 getting to the 'top of his engine quicker' than my Group IV Fuchs 5w30 full synthetic in winter.