If you travel a lot... And I know coverage is an issue especially in the Rockies and west... Could you go T-Mobile?
With T-Mo's Simple Choice plan you automatically get free text and data in over 150 countries. I used it in Italy for 32 days and it was great. Data speeds were not LTE, but usually H+ and everything just works. No set up, no switching SIMS, no logging travel plans. Just go and use your phone.
Add Skype for calling and it only costs a minimal amount.
Something to think about for the future.
Lumia 830 seems like a solid all around phone. The 930 is a high end unit to be sure, but you won't get LTE when stateside... If it were me, I'd pick 830 for the microSD slot and the way less power hungry screen. 930 has a reputation for eating battery pretty quick.
Nokia Lumia 830 vs. Nokia Lumia 930 - GSMArena.com
The Factory Unlocked RM-985 Lumia 830 sold through B&H reports to be LTE compatible in the US by users in this forum.
Nokia Lumia 830 RM-985 16GB Smartphone A00021287 B&H Photo Video