I am looking for input on the cabins in Ms Treasure. We have decided on this river trip and I am down to picking cabin. We have never river cruised and only one ocean cruise. Cat 2 is bottom level but 33 sq ft bigger. Cat 3 is small at 150 but with a full window but in back of the boat. Is Cat 4 on Ruby deck at $1300 difference worth it? I'm not being cheap but more looking at how much time we actually spend in room and I don't want this to make or break a great experience. We are on our 4th Tauck trip and after business class etc. just want to spend wisely. Thanks in advance for any input on your experience on this vessel!!