Invoice pfds the "ProductTableNew" has some issues.
most important is that product comment is missing.
please see here:
http://www.screencast.com/t/L3VdnYmiudL
Function "ProductTableNew" is editable by system admin and you can modify https://github.com/YetiForceCompany/YetiForceCRM/blob/developer/modules/Vtiger/pdfs/special_functions/ProductsTableNew.php as you need or add another one. There is a simple sample of this product table.
@lalord if you need remove some columns, try remove field in advanced block.
