You will not stunt is growth. At 17 months he's a good age to neuter. Most of his major growth is all done...and he will continue to fill in even though neutered. He also will not get into the bad habits of marking, and urine licking that intact male dogs do. You may not even see much of a difference....though I think their ability to concentrate does go up. No 'girlie' smells to get them all excited.
On the whole from what I have seen in my own male Rottweilers, and the many males that I have fostered (often given up because of problems because they were still intact)....they are just easier to live with.

Let us know how it goes.
P.S. 101 lbs is a nice size Rottweiler...he will probably finish at 110 lbs or so. Good sized, in standard for the breed.