Mobil 1 is at least as good as Valvoline conventional oil but the difference does not justify the price unless you are a NASCAR fan, then it's ok. For about a buck more a quart you could run RLI. For a lot less you could run something like Motorcraft. How bout Valvoline synthetic or Pennzoil synthetic, cheaper than Mobil 1 and though to be a better oil by many here.