I am leaning Davis for this year but not a wide margin. How I view things, he is markedly better than many people think and he has time in the league. While some do not think / care / worry about that, I personally always give more weight to people with time in the NFL when comparing players without. There are many folks who look great in college but do not translate, or take a bit longer. I prefer taking the known commodity with NFL experience.
I think Montgomery and Davis are actually pretty similar as talents. But I do think Montgomery over time is likely the better if only slightly. So for this year, I think Davis will probably have a better year (redraft), but long term (dynasty) I would be taking Montgomery. Though admittedly it might not be a landslide and the balance for both will possibly be shifting from start to end of season.
To your questions:
Slightly more points
Starting as Team RB1
Slightly more snaps by end of the year
Lower in drafts, especially Dynasty
Mainly, I was only putting it out there as an update. I did not think they were going to go RB, and especially that early given their picks were slim. With redraft, I would take the value on Davis but with dynasty I would go Montgomery. It was not clear what format for the initial question, so I was trying to answer a bit better after the draft.
As always, these are just my thoughts and I know many folks have other views. Just figured I should give my thoughts to the question and, at the least, give something to think about 