Or buy $3600 of tickets at southwest.com.
That's a lot of tickets for most folks to use in a year! Note that southwestgiftcards bought at southwest.com qualify for the double earnings rate, and carry no expiration date. Charges with preferred hotel and car rental partners also earn double credits on the Signature card.
The difference in earning pays for the extra $20 in fees if you spend over ~$1500 per year at southwest.com.
There is little reason, IMHO, to factor in your annual spend rate at southwest.com and preferred partners if you are going to carry a RR Visa. The two anniversary bonus credits, which also are not given on the $39 card, make the extra $20 fee worthwhile for anyone who considers an award worth $160 or more.