Prices are based on the amount of traffic each option sends. I go by what the other buyers tell me and you pretty much get what you pay for and some. I've had people advertising with me for years (same people) with no complaints.
With getting TONS of people a day and 100s of thousands page views a day you can get your site as popular as you want buy just paying a fair price.
So navigate the options page and pick out want you want.
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