Yes i think you are correct in the only real difference in clearence.
Yes i do think the 1617 is a newer prop that came out to combat the ballast systems people are running. Its very simular and really other then it being quite compared to my OJ i only felt a difference when the boat was loaded down.
My buddy said he feels like it pulls harder from a stop at the end of the rope and this maybe true as this year was the first year i ran it and also the first time i have injured my shoulder getting pulled up from a stop.
Normally i would have let go with a hard pull, but i was also determined to get wake skatting down and the board i was using is a PITA to get up on. So i was holding for dear life and didnt want to let go LOL