I upgraded my bow sight and rest a couple months ago, and my shooting seems to have improved dramatically. I'm using a PSE Whitetail Extreme and had the rest and sight on it that came with the package from BPS. I changed to a Trophy Ridge Nitro Extreme 3 pin sight and a Whisker Bisquit rest.
By the way, I was disappointed in the Nitro Lights - they don't seem to make any difference in the brightness of my pins at dawn or dusk. Also, I had been told by several people that the WBs tear fletchings off the arrows. The guy at Bass Pro told me to put a drop of fletching adhesive on the leading edge of the vane to prevent it. I've shot about 200 times with the same four arrows, and haven't had one come off yet.