One reason I don' t use them is because I have enough stuff moving on my bow - without having the sight move also

And the most important is I do 90% of my practice from the ground - either in the range or in my back yard. I like to shoot 5-spot targets at 40 yds - and the percision of a good fixed pin sight(spot-hogg) cant be matched by a pendulum. Also I often practice out to 60 yds or so and the fixed pin is just much better for this.

I use one pin for hunting out to about 35 yds, and another set at 40.

No reason to change.