We just got back from the Galapagos with Silversea and had an amazing time. It exceeded our expectations which were very high. I read many of the reviews on CC before the trip who were not happy with the service on the ship, our experience was quite the contrary. The service was first class and we felt pampered and appreciated at all times. I cannot think of any issues we had on the trip. The food was amazing! Ever meal topped the previous one and our executive chef on board even gave us many of the recipes. We had one person who had a gluten free diet and they baked us gluten free bread every night for dinner that was hot and tasty. If you always wanted to go to the Galapagos I could not see a better way to experience it then the Silver Galapagos.
The expedition cruise may not be for everyone though. We absolutely loved it, but you do get up every day for ~6:30-7am breakfast and then go on 3-4 excursions per day. We hiked on volcanic mountains, snorkeled, kayaked, went on Zodiak rides for wildlife, played with sea lions, turtles, penguins, blue footed boobies and so much more. We would typically do 1-2 excursions in the morning, come back for a nice lunch on the deck with wine of course and then 1-2 excursions in the afternoon. After a great dinner we would retire before 1pm as we were beat. You don't have to do every excursion but to me that is what this trip is all about. Many days you have multiple options on what to do. We met so many nice people from around he world. These expedition cruises are more active and thus attract a younger crowd than normal for SS, most people in late 50's or 60s probably.
The rooms are smaller on these ships but very nice. We really spent very little time in the room except to sleep. You don't need to upgrade the room unless you really just want a ton of space, the standard room will work just fine. we were in cabin 345.