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Obviously the latter is better from a branding perspective and people are more likely to type it when they revisit the site, but from a SEO perspective, which is better?
The main advantage I know of with hyphenated domains is when there's a direct URL link using the domain name they're separated but that doesn't happen a majority of the time. I try to keep hyphens to a minimum possible and frankly think domain names look much better without hyphens.
More hyphens may cause problems. Recently I submitted one of my 5-word domains which has 4 hyphens between the words, and several (secondary) directories rejected it outright. My actual domain and website has nothing spammy about it, but there have been so many spammy domains abusing the hyphens, that I see where these directories are coming from.