Was curious about the Nema17’s … Will you be using the 1.8 degrees or 0.9 degrees version?
1.8 degrees 
0.9 provide more steps and theoretically more accuracy however this gain is at the expensive of speed, and the torque falls off quickly if you go too fast.
The motors we have selected are the best balance we have found without moving to servos.
Our motors at 1.8 have an impressive rpm for a stepper and good torque.