The “best practice” is use lower case field names since this allows one to change databases, should the need arise. The “Display Label” already removes the “_” from any of the field names. It would be really nice if it would convert the text to camel case while it’s at it.
If you type field names in the following format “Camel_Case” it will automatically remove the _ for the display label and then convert the field name to be lower case automatically.