Hi. I guess I will try. I have been an iPhone person since iPhone 3 that came out in 2008. That made me an AT&T customer. Sprint is saying that by the end of June 2013, they will have a great amount of LTE activations, and the rest by the end of 2013. I am thinking 70% of the major US cities will be LTE by the end of next June, with the rest to follow by the end of next year. So,if you get the Sprint iPhone 5, it will offer 3G regular, not 3.5 or HSPA which is what T offers now. Sprint has not identified the cities it will roll out, except we know Chicago is due at the end of this year.
I have an IPhone 4 now, which only runs on T's 3G service, not HSPA, which needs an iPhone 4S. I have been very happy with the iPhone 4 anyway on 3G.
If you want LTE now, you would need to go to VZ or T and see about what they offer in Portland.
But they charge more than Sprint,who has an unlimited plan.
You should find out if you can run your medical apps on any iPhone. Ask the co workers and the employer how the iPhone is doing. Maybe you have to just use a BB phone for work and the iPhone for personal. Up to you I guess on what is best there.
Maybe you can visit the Apple Store in Portland and speak to them on your medical programs to see if they can be run on Apple.
As for 4G LTE, honestly, I don't know how much better it is. For myself, I plan to get the iPhone 5 at AT&T later on in October when it will not be so busy, etc. I will just go with the flow and get one anyway, as I just hear 4G is really much better for speed and watching videos.
Hope this helps. Good luck on how you work it out.