I've got Silk Kimono & it's a very fast-growing plant, and to me it has an elegant appearance. It has an amazing glow in early evening light. Must be where I have it situated, but no other hosta I have has that same soft appearance in the evenings.
I've seen one Satisfaction that was on the ROHS tour in 2006 that was a show stopper.
I had no idea it could get so big until I saw that one.
And the others are right - they don't look alike at all. So if you've got the room, you definitely need both.