I've been using NHSEO for awhile now and like it. I tend to use it to blast my web 2.0s, FB page, articles etc. I don't use it on my money sites except for micro niche sites that I don't care about.
As for results, it's hard to say because as I said I don't aim it at my main money sites. They have moved up a lot recently but I've used many different services and tools so can't say which is working better than the others.
I just like to have a mix of links being built all the time. NHSEO fits perfectly into this. I hardly check it and let it run all day and night. I'm not sure how much benefit blog comments and forum posts using Xrummer give you these days. But as I said, it all adds to the mix.
NHSEO is a one time fee and is upgraded regularly. Would I use it if it was a monthly fee? No. But as a one of fee and really set and forget you can't go wrong at this price.
If you do go with it, take some time setting up the websites in the beginning. A lot of people who complain about it probably enter their url, pick a keyword, use generic spun comments and press go and then expect links appearing on PR4 pages.
There's a lot of fine tuning you can do to get the best out of it and it's worth reading the manual, seeing what others suggest and set your sites up correctly. You'll get far better results if you learn to use it to begin with.
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