Which safe harbor to elect "IRS Notice 2019-07" or "Revenue Procedure 2019-38"?

I have a few residential rental properties in the US. This has been my main source of income for several years now. In order to qualify for QBI deductions, it seems I must choose one of the 2 safe harbors listed on the subject line. Is this correct, or can I still qualify for QBI deductions without electing either one? Even if I don't have to elect a safe harbor to qualify for QBI deductions, is it advantageous to elect one?

 

If I have to choose one of the 2 safe harbors, then which one is to my advantage? How do I determine which safe harbor is better for me?

 

Thank you!