I have the 717's which I love. My foot doctor has the 1000 or something or another of New Balance, which she recommends, but my wallet didn't. The higher the number shoe, the more features it has is what the saleswoman told me one time.
My daughter has plantar facitis and she bought the 926's (because she was also told they were good for plantar facitis) and for some reason didn't like them and sent them back and got the 993's and love's them. The 993's are supposed to be like the famous 991's. The 992's were a disappointment so they re-made the 993's to fit more like the 991's. How's that for info. overload?