Nintex 2013 - Field Is Null Versus Field is Blank?

I have a SharePoint list where I'm running a site workflow on.  In the list I have a simple Single line of text column that holds an email address called "Company eMail".  In the workflow I have a Query List action and I need to filter on the list and grab the list item if the Company eMail field has something in it.

The question is do I use;

1.  When column: Company eMail is not null

or

2. When column: Company eMail is not equal to 

and I put nothing into the is not equal to field.

Thanks,

Andy