I went on the same boat last October and booked again because every single aspect of the trip exceeded my expectations. The itinerary and staff ratio led me to book the first time, but the food, accommodations, and crew made it an easy choice for trip #2. The islands are wildly different depending on the season, I definitely recommend going more than once!
The guides are excellent and the small groups lend to not only seeing the animals up close but also amazing pictures. If you're into focusing on the scenery other guests are always glad to share photos (airdrop saved me this trip as I left my DLSR at home).
I've done both trips solo but would also return for a 3rd (or more!) trip with a friend or my boyfriend. I'm sure a +1 would be great but as for solo trips, booking with Quasar is by far my favorite. The other guests are good fun and every detail is handled making this the most refreshing week ever. I love that there is no guest phone/wifi service on the boat, I hope that never changes.
I stayed in D4 my 2nd trip and C6 on the first trip. I was only in the cabin to sleep but it was comfortable, very clean, and had everything I needed. There was plenty of room and storage.