Performance of Feature Class To Feature Class (conversion) or Table To Table (conversion) tool is slow when exporting to shapefile or dBASE (.dbf) if the input is a geodatabase feature class or table with attribute domains.
When converting a geodatabase feature class or table with attribute domains to a shapefile or dBASE (.dbf) table, the domain codes and descriptions are included in the output. The descriptions are stored in new fields with "_DESC" appended to the field name. The process of exporting the domain descriptions to the output is very slow.
Performance of domain export is expected to be significantly improved in ArcGIS 10.0 Service Pack 5.