PRWeb vs WebWire - Case Study and Questoins

I have a client with a biotechnology product that we are marketing online. I submitted 2 different press releases to PRWeb and Webwire 3 days ago. I am trying to decide which one is better.

Here are the results so far.

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Prweb - cost $200 (I actually found a $50 coupon, but it's 1 time use, so I'll use the regular price here)
Google shows indexed distribution on other sites - 212 results

Very important - most of these are industry specific blogs on biotechnology, ecology and other technology (basically a lot of "ology"), Dallas News, Yahoo news and a few news aggregates.

Full page reads - 504
Interactions - 54
Direct traffic to website according to Google Analytics - 22 visits
Direct traffic to website according to Awstats - 50 visits (seems more credible due to number of interactions above)

Webwire - cost $24.95
Google shows indexed distribution on other sites - 51 results

Only a couple are industry related sites. Most of these are other news aggregates, and completely unrelated sites such as a canadian pharmacy, jewelry blog, forex site and such.

Full page views - 402
Interactions - 33
Direct traffic to website according to Google Analytics - 19 visits
Direct traffic to website according to Awstats - 24 visits (seems more credible due to number of interactions above)

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Total traffic went up from different referral sources, but I don't know which PR they clicked on (looking back, I realized I should have used different landing pages with a redirect to track this - oh, well, next time...)

I'm not looking to use press releases to just generate numbers of backlinks - I get a ton of them in other places. My goal is to generate actual targeted traffic.

So the big question to all of you who use press releases for generating traffic - what is more important - the syndication aspect or the direct readership?

If you consider only the page reads and clicks, webwire is the clear winner here financially.

However, syndication-wise, webwire is not doing much. However, Prweb got this press release on VERY targeted industry websites - and I'm not talking about somebody's blog with a ton of articles and affiliate links. Some are educational in nature and couple are international associations for specific industries that use that type of technology.

I'm thinking is that Prweb is the winner here because it got the press release into the sites that have targeted visitors. Even if half of those 212 sites are not targeted, we are still looking at 100 placements for $200 - that's $2 a press release.

In addition, they have packages for companies that submit a lot of press releases. The one I was offered got the cost of the $200 release down to $77 (which changes all the ratios dramatically).

Also, I do understand that the true syndication (sending individual articles and press releases to companies) is the best. I'm planning to contact some of those places that already posted a PR and offer them some exclusive articles to publish. But this question is directly related on online PR submissions.

I would love to hear some thoughts and opinions.

Katerina