First of all, press releases ARE very good for communicating directly to customers, prospects and the media. Some of our clients get news briefs just by issuing a press release over the wire (if the news is relevant, which is whole other discussion). Press releases also provide valuable backlinks to your site, and build credibility for your business. Your prospects will certainly search for info about your co on the web and it's great to have a press release on dozens of news sites.
That said, with newswires, you get what you pay for. I would recommend going with one of the big three -- PR Newswire, Business Wire or Market Wire. I have most experience with PR Newswire and Bizwire. You also get great reports!
You will have a better chance of the media seeing your press release with one of the paid services AND they distribute to thousands of sites, providing valuable backlinks. Some of the Internet press release services do not have the same level of stature with the media IMO.
They also have professional editors who look over your press release - but they do not write it for you. That being said, be careful to write your release in an editorial style, not marketing speak, to ensure the media takes you seriously.
For more tips, you can visit my site www.WebPRpro.com. Happy to help. Good luck!
Bonnie at WebPRpro.com