I have both the Shinn sneaker 5 and Naish Apex. Both feel pretty different but both are comfy and lock your feet in quite nicely. Sneaker 5 has this extra bumb to put your feet over, which is nice for extra grip. Sneaker 5 screws do come undone quite often though while riding, resulting in a half-attached binding, so best to tighten the screws once in a while. That being said, when they do come undone on the water, the screw itself stays in place in the binding, and doesn't fall out, so I have never lost a screw because of this.
Long story short: Sneaker 5 are comfy and lock in quite nicely so no need to buy another binding imo, but remember to tighten the screws regularly.