[aiharkness]

I don't have experience with the others, but I did use an 8820 for a few years, and my wife uses it now. Is is a solid divice. The 8800 is an old, old device in smart phone terms, and I don't think it has wifi capability. Browse the for sale items on the forum. I would think even the 9700 is getting into the low price range for used devices by now; maybe not down where the 8800 is at, but then it isn't antique yet, either.

Be careful about buying used BlackBerrys. See the article about buying one via eBay at blackberryfaq.com. It applies in general to buying second hand.