As you can quickly see the cheapest solution is going with Apple / AT&T - which for 3 years is $1000 cheaper to own and operate on AT&T than on Sprint or Verizon. It is also the most convenient solution as there is no extra hardware to carry around as is required by the other three solutions. However if you are looking for the fasted connection speed. Then you will want to look at the 4G (WiMax) solutions from Clear and Sprint. But note with both Clear and Sprint when you are not on the 4G network - then the data is not unlimited. You have a 5GB cap on the 3G connection or 300 MB/mo. while off-network roaming. Additional monthly usage over 5GB costs $0.05/MB. You may not use more than 300 MB/mo. while off-network roaming.
My recommendation - If you want the simplest and cheapest solution - hands down go with built in 3G and AT&T.
If you do not want anything to do with AT&T or want the fastest solution then Clear is the next best option.
But each solution does have it pluses and minuses. Here they are to help you decide for yourself.
Apple / AT&T:
Pluses: Cheapest solution by a wide margin. Most convenient solution - All in One. Best for the road warrior that cuts the handles off of tooth brushes to save on weight. Never any overages if you go with $30 plan. Very easy to turn on and off 3G plan so you can save even more money or even go with the $15 a month plan for very limited bandwidth (250 MB).
Minuses: If in NY or San Francisco - AT&T - enough said. Need to wait until late April for your iPad.
Pluses: Fastest connection speed (same as with Sprint) WiMax. Cheaper than Sprint and Verizon. Can go month to month with data plan. Can use 4G/3G modem also with your laptop when not using iPad.
Minuses: Very limited 4G coverage. Data cap on 3G coverage area with $0.05 per MB fee after cap is reached. Need to buy both a hot spot unit ($140) and a 4G/3G modem ($225) - on top of the iPad - highest up front cost.
Pluses: Overdrive is one device ($99) so lower upfront cost vs. Clear.
Minuses: Very limited 4G coverage. Data cap on 3G coverage with $0.05 per MB fee after cap is reached. Most expensive solution. Over $1000 more than Apple / AT&T solution for first 3 years.
Pluses: MiWi is a single device and cheaper ($50) than the other options. Verizon 3G coverage is the widest of all the options.
Minuses: $1000 more over 3 years than AT&T option with a slower connection speed than AT&T 3G. Data cap of 5 GB per month.
NOTE: The cheapest solution overall really is just getting the $699 WiFi only iPad and not getting a data plan. This post is just on comparing the iPad for those that must get a data plan or feel they must get a data plan.
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