We love the S class ships. Typically book a suite- we will sail on the Silly in about two months. Reflection and Silhouette our favorites as we enjoy the Lawn club grill. The Equinox was also great, but once you do the glass blowing, not again, IMO.
We recently sailed on the Apex. Sister of the Beyond. Hands down the ship wins. So if you enjoy time on the ship, dining on the ship- The e-class cannot be beat. If its all about the cost and itinerary, do what works best for your budget.