Wal-mart does have the Pennzoil Ultra Platinum (The new Ultra) 5W-30 in stock at the Franklin,LA store, and the Opelousas store apparently carries it too but is currently out of stock. I'm jealous, apparently there's not a store within 120 miles of me that even carries it anymore!
As far as comparing Mobil 1 EP to Ultra/ Ultra Platinum, I think you'd be fine with either considering how new your car is and your desired OCIs, I'd go for whichever was cheaper. They're very close in quality and performance from everything I've read on here over the last few months. I'm in the belief that Ultra would be better for a high mileage and/or dirty engine because it has more cleaning additives in it and it was designed to keep your engine cleaner, but EP would be better for long OCIs (above 7500 mi) since that's what it was designed for.
Pennzoil Platinum would also be a good choice, it's nearly as good as the Ultra/ Ultra Platinum and in some weights might even be better.
Quaker State Ultimate Durability will also serve you well,
especially with the short OCI. It's a more wallet friendly quality oil.
Castrol/Valvoline: I can't tell you much about these, I've used Maxlife a few times and it seemed okay, and we used GTX High Mileage in our older vehicles and they worked fine, but I've never used Valvoline synthetic and the Castrol synthetic line has gone through multiple reformulations since I last used it.
My vote: Pennzoil Platinum or Ultra Platinum. With the current promotion Shell has going on right now, you can save $1/gallon with the purchase of a 5qt jug of Platinum or Ultra Platinum up to 20 gallons of gas, effectively making your oil cost roughly 5 dollars if you pick up a jug at walmart and buy a full 20 gallons of gas. O'Reilly auto also has a deal going on that you can get a 5qt jug of Platinum and a filter for 35 bucks with a 15 dollar rebate, add that onto the fuel savings offer from Shell, and bam, free oil change! Not to mention that your car, being as new as it is, is eligible for that warranty deal if you use Pennzoil or Quaker State oils. I'd like to have that just in case