The larger cities in Montana certainly have the qualities of typical "great" downtowns. You'll find a density of business, culture, and retail in Missoula, Bozeman, and Billings, but in Montana, I don't think that's what necessarily makes the "best" downtown.
Montana actually has our own Benghazi Memorial in Bigfork, Montana. Retired Navy SEAL and former Trump Interior Secretary Ryan Zinke was there to honor the fallen in Benghazi on Sunday. Meanwhile, Zinke's Democrat opponent gets hit for "tasteless" 9-11 social media post.