Which iPad 2 Should You Buy?

With the iPad 2 launch just days away, it’s a good time to consider which iPad (s aapl) model you want to buy. If, like me, you plan on upgrading yearly and taking advantage of the iPad’s excellent resale value, it’s crucial to be aware of what models are popular, and you should also consider your usage habits in order to decide between 3G or Wi-Fi only connectivity.

16 GB FTW!

NextWorth, one of the many companies that offers cash for used electronics, has recently seen a five-fold increase in the number of iPads being traded in. Not surprisingly, the 16 GB iPad is most popular, making up just under 40 percent of trade-ins during the first four days of March, with the Wi-Fi version accounting for most of those. The 32 GB and 64 GB models roughly split the remaining trade-ins, though somewhat surprisingly, the 64 GB 3G was second in popularity. For those considering selling through NextWorth, the resale price of the 16 GB model was around $255 as of last week.

Looking at eBay (s ebay) today, the distribution of iPads being auctioned is similar, with the 16 GB Wi-Fi iPad again being most popular. Resale prices are higher on eBay than on NextWorth, with 16 GB Wi-Fi iPads selling for an official average of $420.78, and the 32 GB and 64 GB models adding approximately $50 and $75 respectively. 3G adds another $25 or so to the asking price. Keep in mind that selling on eBay entails more cost and risk, and that there are other options.

While these numbers only show what people are trading in, they also provide a good representation of what they’re interested in buying in the first place. The numbers may change with the iPad 2 as people realize they need more storage or better connectivity, but the bottom line is that it shouldn’t be hard to find a buyer for a 16 GB Wi-Fi iPad, even if these numbers shift slightly over the course of the next year.

3G or Not 3G?

If you plan on owning an iPad 2 for years or more, the extra connectivity of 3G is worth considering, and as an added benefit, the 3G iPad also features true GPS. Unfortunately, for U.S. iPad 2 buyers, that also means choosing between iPads designed specifically for either the AT&T (s t) or Verizon (s vz) network.

Setting aside coverage issues, comparing plans comes down to price and data. AT&T offers the cheapest plan at $14.99 per month for a measly 250MB of data. Nonetheless, if you get by on that with an iPhone, it’s worth considering for an iPad, but note that for just five dollars more Verizon offers four times the data. Also worth considering is speed, where Verizon still lags until the iPad gets LTE capability. Unfortunately, neither company offers rollover data like rollover minutes.

Which is Right for You?

The takeaway is that if you plan on upgrading your iPad yearly, the 16 GB Wi-Fi model will likely offer the best return on investment. Those planning on keeping an iPad 2 for as long as possible should consider the model with the highest storage capacity they can afford. While rumors of an iTunes cloud service would make storage less of a necessity, the likely reality is that Apple will offer unlimited downloads rather than storage-saving streaming, at least for the foreseeable future. Also, increasingly rich and sophisticated games like Infinity Blade need between 500 MB and 1 GB of storage today, and requirements will only go up from there. More storage is a good long-term investment, and so is 3G capability.

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