Email From & Sender fields · How to use?

Please help me understand the best practice use of the two fields From and Sender in the Email module.

From reading google’s documentation the Sender field will be part of the header, but hidden to the recipient. Regarding SPF it looks like it is recommended to keep the Sender identical to the actual sending email.

I also noted that when sending to Gmail it is only the name in the From field that is used. The provided email is ignored.

I’m currently considering changing both From and Sender info back to my actual email info, but would love to hear some of your experienced thoughts first.