I had a terrible time on the yellow magic cushions, I would say don't bother trying to equate the hardnesses of old and magic cushions. They're apples and oranges, best to wipe your mind about the old cushions and listen to what the nice man tells you: yellows if you're around 170 lbs, oranges if you're around 140 lbs, and reds if you're around 120 lbs.
The yellows were just too hard for me, I could barely lean into the turns on them; they made every practice into an exhausting endurance workout. The oranges seem okay in that regard, definitely squishier than my old cushions. Stay tuned...
ETA: LOVE the orange cushions!
