I ran 606s on my '04 625 SXC.  The front always wash out on gravel.  I bet the same is true for the 690, because they have almost the same fork angle.  On my trial run with the ED77. five of us were on a very fine gravel road with a hard surface under the gravel.  All the others were having trouble in the corners;  I passed all of them having a good time.  The ED77 did great.  I was a convert!