Most companies charge an arm and a leg for SEO services. They promise specific keywords and phases and charge based on their popularity.
More popular keywords have more competition due to the amount of money the number one listing can make. However there's only one website first so hopfully two SEO companies aren't making the same promise.
Creating Visits promises visitors based on variations of your keywords that are easier to rank. The results are quicker on ten small keywords compared to one popular keyword.