Hi Dale. Early reviews suggests that the on ear Momentum is a more aggressive, harsh,er V-shaped sound. I am looking forward to trying one out myself to see, but the early word is that the original Momentum is better.
check out this review
I love my Sennheiser momentum's with my Samsung galaxy 4. They sound like miniature HD 650s, which is why I do not understand why they do not receive more love around here.
I use my Sennheiser HD 598 for tablets and laptops.