Unlimited bandwidth is a marketing ploy. Definitely read the fine print of the user agreements. The host will have some way of cancelling the account for excessive resource usage.

Someone has to pay for the bandwidth. If the site is costing more to host than the webhost is collecting from the customer, then the host will take action to cancel the account.

And also, do you want to host on the same box as others who are looking for and require huge amounts of bandwidth? Your website will most likely experience degraded performance.

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