They have some similarities, namely the natural physical power and difficulty to bring down. What really impressed me with Barber was his nose for the endzone, some guys just have that. Hopefully Mason will as well, but for now what does set him a bit apart is his speed. He has some getup that I don't recall seeing with Barber.
I'm really excited to see what Mason can do with more carries. If you look at the Chargers' defense, for example, they give up a high number of yards per carry given the low number of long runs given up. What I'm thinking is his speed is going to be very dangerous to them, and I could see him going the F off on that defense.
Hope it happens, because man this is a big game for the Rams.