I have worked as a wireless data consultant for several years and as always there are pros and cons for internal and external 3G PC Cards
Internal Cards Advantages, They are less likely to break than a PC Card, are easier to deploy since the software is loaded as well, and will not be lost or stolen unless the whole laptop is lost or stolen
Internal Disadvantages, not upgradeable, usually only work with one carrier if that carrier has poor coverage in your area you are out of luck, can not be shared among occasional travelers, and not transferable when laptop is upgraded
External Advantages, Sharable among different users, easily transferable when upgrading laptops, easy to update to new technology, Choice of all carriers and technologies, ability to purchase one unit for international use and check it out when needed instead of paying extra for international usage on all devices, and usually less costly (estimated cost $50.00 to $0.00, compared to an integrated laptop with card costing approximately $100.00 more than a comparable laptop without a 3G PC card
External Disadvantages, harder to deploy, can be lost, broken, or stolen more easily. May be left behind when needed, and may not be as user friendly as internal cards.
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