Yes - we did the Taormina City on Your Own tour just last month. The experience was fine - basically it's transportation to/from the town. The driver did point out some highlights as we were driving. After arriving, you take the elevator (or stairs) to the plaza outside the parking structure and arrange to meet at a certain time for the return trip.
I thought the time in Taormina was too short. Not enough time to walk around, see sites, have something to eat/drink, and/or shop. I mentioned this to one of the staff at the future cruise desk, and she said they hear that all the time.
I hope that's helpful.