On the Benos Forums there's a Guy that makes really good F.O. Front Sights for the 617: Toolguy is his username I think. Dawson also makes an excellent F.O. Front for the 617 in different sizes.
The Hi Viz are very pricey and the FO Rods can't be changed out on the drop in replacement for the 617 & the M63 because they are plastic coated units. They are also pretty wide which is going to be harder for shooters that need reading glasses.
I agree with posters that say to leave the black patridge sights on a Target Gun. In my mind the best of all worlds is a small red dot optic. They ruin the lines and aesthetics of a fine revolver for some folks, so the next best thing is a good thin F.O. Front that allows you to see a bit of light on both sides of the front sight. The Rear Notch on those Guns are usually .125, so a .115 wide front will still allow good accuracy.
The thing that I have found with the F.O. Fronts is that for precision accuracy, you are still doing what you would be doing with the Patridge sights and that is line up the top of the sight, but now you have a big distraction with the F.O. Rod. Maybe Ed McGivern had it right with just a small gold bead that didn't jump out at you like the Fiber does.
Fiber will also cause Folks just looking at the Fiber to shoot high IMO. For shooting at med. range and further, nothing beats a red dot for shootability.