.com with no dash is always best from a marketing standpoint. People have been programmed to go to "www.xxxxxxxxxxxxxxxxxx.com" and if you throw a dash in there, or a different TLD, you're likely to lose out on some traffic due to people mistyping it.
This is especially important if you are running TV, Radio or print ads, not so much with PPC because people are just going to click on your ad. PPC feel free to use whatever you want. Personally, I don't care what it's for I always go for the .com without a hyphen.