This model is appropriate for project with great web presence. Being also called a 95/5 model, it allows delivering certain amount of bandwidth in a second (for example, 1 Gb per second). This limit can be exceeded, but you are likely to pay more in this case. Suggesting, you order a 1 Gbps CDN and transfer exactly 1 Gb per second, you will have 324 TB in a month. Of course, pipeline will be cheaper than paying for 324,000GB by another model, though, it is not always so.