I have been using a 60 inch Escalera for the last 4 years. I bought it from Larry. It will not damage carpet. I have a nice wool carpet that leads to my basement. I have used the Escalera on it 50+ times. Nothing is marred at all.
I moved a pin to the upstairs at another pinsider's house yesterday. I did it 99% myself. At the top of the stairs there was not much room. This is where I needed a little help with the move. If I was using a the MS 66 Escalera it would have been much more difficult or impossible. If you are not moving Coke machines or the like I do not think you need the 66 inch Escalera.