I have AD2 and it had some unique niches it is good at (14 bits makes it somewhat capable at doing some analysis on audio devices), but I by far prefer to use my cheap-ish scope for near-anything else. Just amount of memory alone is big advantage, higher input range (AD only have like...2 or 3 IIRC, rest is faked by wasting bits on ADC), proper probe sockets without needing adapter, ability to just press buttons and knobs to do what you need without getting back to the computer and going thru menus etc.
Then again, ability to script measurement is also pretty nifty. Can be done on many scopes but by far more effort than on AD