Thanks, it starts to look much better now that I've changed the code to this:

Qt Code: 
  1. QVariant QInt64Item::data(int role) const
  2. {
  3.     if (role==Qt::EditRole)
  4.         return m_data;
  5.     else if (role==Qt::CheckStateRole)
  6.         return Qt::Unchecked;
  7.     else if (role==Qt::DisplayRole)
  8.         return m_data;
  9.     else if (role==Qt::TextAlignmentRole)
  10.         return Qt::AlignRight;
  11.     else
  12.         return QTableWidgetItem::data(role);
  13. }
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But I cant find anything on how to get rid of the check box. My best guess is that it's a call to setFlags() but how?