Is it possible to place a 2 line balloon without the split circle? I would like a balloon that has the part number on line 1, with the description on line 2.
You might be able to make a custom property in your files that's an conactonation of the part number and description properties with a carraige return inserted between them (search forums for examples of how to do this) and then create balloons linked to a custom property.
If you don't need the ability to stack balloons or and don't mind not having magnetic lines, you can create a note instead with the two properties as you described and specify a cicular border for the thing. Save it as a style and use it whenever.
Retrieving data ...