I've stayed at both (albeit a couple of years apart) and would consider the properties themselves pretty similar. They're both perfectly fine, if below average, Sheratons that are showing their age. I agree with Braindrain that some of these posts are a little overblown, and comparing prices to other cities or even Anchorage in November is completely irrelevant - this is Alaska in the summer, after all.

As far as points vs. Airbnb goes, for me it would come down to length of stay. If I were only staying in Anchorage 1-2 nights on my way somewhere else (which was the case when I last stayed there), I'd be choosing a hotel regardless, so the points are pretty good value given how expensive summer hotel rates are. For a longer stay, Airbnb might be the way to go, especially since you could stay somewhere other than downtown.