It’s an easy drive in a Tesla. I’d choose the S because autopilot on that boring freeway drive is perfect. Charge in El Centro at the V3 newer chargers, and then another stop of your choosing. I like the Tacna chargers for their simplicity and well stocked mini mart attached.
On the drive back, be mindful that winds and elevation can chew up your range and there isn’t a supercharger between El Centro and La Mesa - just spend an extra 10 minutes more charging, you be glad you did
On the way east, I’d add about 45-55 minutes total for charging as long as you use v3 chargers