I like the Silver Whisper. The Shadow and Whisper are VERY similiar the Whisper is just newer and some of the decor I like a little better. Either is great.
The Cloud and Wind have some avid fans but I am not one of them. Not that I would say no to sailing on one if I liked the itinerary. I just find the ceilings lower and the ships a little more confining and prefer the Whisper and Shadow. This from a Song of Flower lover sounds really ridiculous. Talk about low ceilings etc.
I think a lot of why we develop love for a particular ship is our memories of our experiences on these ships and the crew aboard.