Valvoline is fine. IMO just pick a brand and weight (10w30 or what your book says] and stick with it plus use a good quality filter. I live down south so I will never use anything thinner than 10w30.
I am still trying to get used to $3.99 a qt oil!
2006 Jeep Wrangler Sport, White/Khaki, Dual Top, 4.0 6-Cylinder, Auto, 3.73 Axles, Dana 44 Rear, Rugged Ridge RC Bumpers, 31x10.50x15's on stock Ravines, Rubicon Fender Flares,