There been alot of speculation lately about hyphenated domains. Most out there are against them, but ive seen instances where they make good sense, just as many of the .com'rs are against .orgs, nets, us etc etc, yet those domains also produce some insane profits. Check out this article for more info..http://greatdomainstoday.com/are-hyphenated-domain-names-a-good-buy/
for seo purposes they are good of course, but remember every extra symbol is pain for type in visitors....
In what way? From a resale point of view or from an SEO point of view? From an SEO point of view, yes. From a resale point of view, it significantly reduces the value of the name
If you want to buy and sell domains stick to the ones without hyphens. If you want to build a site then buy both versions. Develop the hyphenated version for best seo results. The other one just 301 to the hyphenated domain to keep your visitors.
The hyphenated domains are not good to have for a long term business that is trying to build a brand. But for an informational type site that is looking to rank well in the search engines, the hyphenated domains work.
I think hyphened domains are good for seo and to me they with .com are surely better than .net and others.