While b'fast in the Pinnacle Grill is nice (the upgrade fairy once gifted us a Neptune Suite), it seems it really depends on the ship/itinerary if the extra $25 pp cost (under 13 days) is worth it. IMHO, the best benefit is the cabin upgrade, but I can't tell if you book a top price veranda cabin, say, would they bump you to the next category ( a suite?) - you really would have to do the math, or have a TA who would.
Thanks for information, folks.
Sandy