A life jacket or snorkeling vest is a very good idea in Komodo, even if you are a capable swimmer. At calm sites you may not need the extra buoyancy, but at current-sensitive locations it reduces fatigue and gives you a margin of safety if the water starts moving faster than expected. It also makes you easier for the boat crew to spot at the surface.
Strong swimmers sometimes avoid flotation because they want to dive below the surface. That can be reasonable at an easy site if the guide agrees, but confidence should not replace local judgment. Komodo currents can be deceptive, and a person who spends twenty minutes swimming against them can become tired surprisingly fast. A vest lets you stop working and simply float while waiting for the boat.
The important detail is fit. Make sure the jacket is the correct size and that straps are secure before entering. Children need child-sized equipment. If your operator’s gear looks damaged or does not fit, say something before the boat leaves the harbor. Safety equipment is most useful when it is comfortable enough that people actually wear it.

