Thanks Sway! You are right, the larger zebra plant in the backround is from a friend, I just placed it with the others, and didn't even look that closely at it until now
I'm glad to have some of both types!!
The only thing I want to correct you on is the one you called 'Grey Ghost' mine is 'White Ghost' and they are different plants!
I called mine a retusa solely based on the internet...it came from www.absolutelycactus.com which is a great place for cactus and succulents! (small family owned, organic, and conscientious about where they get their plants - most of them are seed grown by the owners themselves!) Anyway my plant was only labelled 'White Ghost' but then internet searches came up with retusa 'White Ghost' so thats what I've accepted it to be!
I'd love to see more of your plants!