I just had one this past weekend--flew into Tampa, drove up to the Orlando area, back to the Zephyr Hills area, and back to Tampa. It was a glorious day, high's in the upper 80's, and it was wonderful to have the rag top. I wasn't hot at all.
I did get sunburned from just driving around.
Keep in mind that you lose a LOT of trunk space with a convertible. It was just me with my tote bag (24 hour trip!) so no worries. But that trunk isn't going to hold more than a couple roll-on bags and a couple tote bags.
I had a Mustang, which is a little smaller than the Sebring, but even the Sebring is going to have limited trunk space.
Also, your DD's will not be able to have any activities, toys, etc. in the back seat with them. At 70 mph with that top down, even an empty cup in the cup holder will start to fly around!
You need to make the decision yourself, but those are some experiences to think about.
Have fun!
Anne