I researched the Pirelli's also before purchasing the Ascent's. In my 295/70r18 size they both weigh in at 57 lbs. I got a much better deal on the Bridgestone's through DIscount Tire. The Scorpions were my #2 choice.
Look at the Bridgestone Dueler Ascent. Lightest 34, 18" tire in E load in those sizes. It's an amazing tire. I wanted k03s too until I saw the weight. Almost 10lbs less per tire!
I just recently purchased a TRD ORP (love the shit out of it!) and was also considering pretty much the same Ram you're describing. The biggest deciding factor for me was resale value and reliability. Dodge trucks (except for diesels) lose a lot of value as soon as you drive them off the...