OK, finally got some nice weather for some shooting, so I took out my two bows that are of equal draw weight, but different taper rates (0.002 vs 0.005 total taper), and shot them side by side with the same douglas fir arrows.
Qualitative Results....
*I really can't tell any difference in the smoothness of draw.
*Cast appears to be equal by my eye.
*Arrows flew the same out of each and hit with the same accuracy out to 25 yards (as long as I did my part).
*My newest bow with 0.005 taper rate seems to have a little less thump upon release, but not a big difference and I probably wouldn't know the difference unless I were shooting them side by side.
I need to hook up with somebody with a chronograph to get a real quantitative comparison, but as far as overall shootability, I can't say there is much difference.