We've tried rental car, limo sevice &
DCL buses & find DCL the most convenient. If you're staying at the Hyatt the night before, you can just leave your bags in your room & they appear at your stateroom door.
Also if you're flying a participating airline you may qualify for Onboard Airline Check In. On the last full day of your cruise, they deliver your boarding passes & special luggage tags to your stateroom. You just put your tagged bags outside your door the last evening and don't see/touch them until you arrive at your home airport the next day. Just hop on the bus with BPs in hand and hop off, head to gate. So easy & a great way to end a nice cruise!
With a rental car, you might save $30 but you'll have to retrieve your bags from the terminal warehouse area, wait for the rental company shuttle, lug your bags on & off the shuttle, wait at the rental office, cram the bags in your trunk, wait in the long CASH line for tolls, driving is the easy part!

refuel the car, save the receipt to prove it, drop off car, gather belongings & lug bags to terminal, check bags, then head to gate. At some point, this stopped feeling like we were on vacation.
That's the simplified version. I didn't mention in all of our time waiting for & getting on & off shuttles & in & out of car, ds lost his Nintendo DS. Also our rental car had another rental car park so close, we couldn't open either door enough to get in. (We're not big but neither could my then ds10.) It was literally 5 inches space. Had to wait for office personnel to come out and move the other car. Then we could see lots of damage
not noted our our slip. So in we go for a 3rd time to the office.

By the time we got on the road, my parents were probably already at MCO. All that to save a couple bucks?

No thanks.
We're a family of 4 and I don't mind paying a little more for DCL transfers. To me, it's worth it.

$35 pp each way. Doesn't have to be RT.