I have been 90% satisfied since replacing my netbook with an iPad 2. In fact, if I did not teach math, the iPad would easily meet 100% of my expectations.
The main reason I got an iPad was the instant on feature. A simple task like checking email was a 15 minute ordeal on my netbook. Now it takes less than a minute.
Doing lesson plans on my iPad is so convenient. I use a Numbers spreadsheet to schedule my lessons, then save it in Dropbox.
I also like the simple functionality of Pages as a word processor. The only complaint I have is that there is not a word processor available for iOS (or Android) that has a built-in equation editor. I made a video and posted a description of how I intended to work around this problem, but it is just not practical for a math teacher.
However, in my case, the pros outweigh the cons. I get a lot more use out of my iPad 2 than I did my netbook. I’ll just cross my fingers and hope that some day, someone will make a word processor with a built-in equation editor.