I agree with the above, however, I would also say it depends on the amount. If you overage 100 GB a month, you might be better off upgrading to the next package as you then get extra RAM and disk space on top of the extra bandwidth - for the same price.
On the other hand if it is only a few GB's, you might be better off just paying the overages.
However, else, I agree with the above reply.
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lakridserne
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