The title sounds like a guided tour, but we rented the bikes and explored the island independently. As a casual cyclist, I have considered E-bikes 'cheating' but conceded (this once!) because of some health issues.
We stayed conveniently across the street and happened by the evening before our ride where a very high energy guy whipped through dizzying instructions, however when we picked up the bikes the next day I asked a few questions and felt far more confident and comfortable.
My first bike made loud clicking noises - my husband checked it out and we turned around, and traded for another bike, no problem.
Car drivers were as careful and respectful as we were - very comfortable to ride on streets. We went to the sea wall which is wide and easy to share, then caught the ferry (easy on and off - free - well organized) to Bolivar Peninsula. The main road is shared with vehicle traffic, at first with a narrow area for bikes, but widens later (there is an asphalted strip along the highway but it's rough). Rode to and around the bunker park - had a picnic lunch, then returned. All told, there and back to the shop was 5 hours, but can be done in 4 if we didn't include the sea wall.
We rented the bikes for 24 hours, the hotel kindly stored them overnight for us and we took a morning ride along the wall before checking them back in. Our original plan was to return the bikes after our trip to Bolivar, but Zipp guys encouraged us to keep them for the rented duration and we were really glad we did because the morning ride was beautiful and refreshing.
I HIGHLY recommend renting the bikes, and Zipp E-bikes in particular. The bikes are well maintained, the location worked wonderfully as we were staying downtown (even rode them to dinner!). We took our own helmets and lock, but they will provide those if needed.
So....cheating? Yes, kind of - but also LOADS of fun, relaxing, and we will certainly do it again in the future.