They look a little scammy - they never actually explain what they do on their website. If you are looking to hire an SEO, make sure you ask them alot about what they're doing first. You don't want them trying any black hat techniques that can penalize your site.
I have never used this service before, you should be cautious because many of those services will not produce the results they are promising you.
I thought they looked a bit scammy also as they sell a link building service, but have no links to their site and they have testimonials, but the site has only been live for 1 month and they only bought the domain for 1 year... Yeah, I think you are right! Thanks guys for the feedback.