The calculator that not only do I own from years ago, but also provided to students in most cases (could be this one or the more comprehensive ones) as part of the mathematics courses on the high school level. It's durable alright, seeing as the one I have has been dropped about literally a little over 30 times, and right after each of those "drops" would see the calculator running normally, as if nothing ever happened. As to the physical damage - let's just say that that's a whole different story.
Amazingly enough, this still works as it did on day one, and it never fails to provide the required assistance when it comes to homework assignments from courses such as pre-calculus, algebra (advanced - either way regardless, this calculator's always there to give you the necessary assistance) and calculus, just to name a few.
The TI-83 Plus provides the user with a whole load of sophisticated and comprehensive, more advanced features, which are of course "there", just in case "if ever needed", as much as one may think they won't need if they're thinking about pursuing a more cheaper calculator that simply comes with functions such as the sin, cosine, and tangent (most common ones).
This comes to be the case only to find themselves struggling to find "where the heck are the graphing functions?" - when in fact, that's nonexistant. It's worth every cent towards buying these comprehensive calculators because not only does it provide the user with a bunch of features as well as a graph link cable that allows the calculator to be connected to a computer, (as previously mentioned in regards to features - but just to name a few, things like fraction conversion, handling of pi, table/chart displays, the ability to use letters for different reasons, and of course graphing, hence it being a graphing calculator) it also gives them the feeling that it'll be there for years and years to come.