I find the charting tool in OOo spreadsheet very frustrating to use.

There appear to be two types of selection: one gives green handles and lets me 
edit the data series: although only by re-defining them as a whole data range.  
There is no analogue of the dialogues in competing products that let you alter 
names and ranges individually.

The other type of selection gives an outline box and lets you use the menus to 
edit the appearance of the chart object: the line style or even the type of 
chart.

I suspect this comes about because the chart object is a separate module, and 
the interface to the spreadsheet is not the same as the interface to the drawing 
setup.  But it is counter-intuitive and clumsy, and switching from one type of 
selection to another is not possible without deselecting: a completely 
non-obvious action.

I have used both quattro and Excel, and the ease of chart modification in both 
is superior.  I am sure I could get used to clumsy techniques in OOo, but that 
does not mean they are not clumsy.