I think we've cleared up the pros and cons of bringing my dog and my planned logistics in the other thread, so how about gear?

Packs: I read that you should buy the pack last, so you know how big you need. True? Or has the question been asked and answered enough times? I like the idea of light. I like the Exos for that reason, but the Atmos and Aether were pretty comfortable, just twice as heavy. I'd like to try on the ULA packs and maybe Gossamer Gear before making a decision. I like the Osprey Any time, Any Where, Any Reason guarantee.
Tent: Already bought. Got an REI Half Dome 2 Plus. On the heavy side, but big. There will be three of us in it with gear, and split between two packs, the weight isn't out of line. Plus REI had a great sale.
Bags: I like the EE Revelation quilts. Mummy bags feel small. We're not starting till May somewhere in the middle, and heading north. Then flipping back and heading south, hoping to be done before the end of October. Seems like we miss the coldest temps at both ends? Do we still need 30 deg bags? 20? Do liners work?
Pads: Leaning towards the Thermarest Xlite. Is the Xtherm necessary for warmth? Are there others out there just as good for less? The Thermarest's seem pricy.
That's the big four.
Pete