Originally Posted by Chris
My advice DO NOT USE METAL D LOOPS. They cost you speed and can damage your bow or at least your arrow rest. I took some digital pics and hope to get them posted soon.
I have exactly the opposite opinion of Chris. Never have had any problem with my metal D loop, and I don't care much for the string loops, though a lot of our local shooters use them. With that being said, our local range/shop has at least two arrows buried in the ceiling insulation from string loops letting go on bows during the draw, flinging the arrow up into the ceiling, and I've seen numerous other string loops come undone at the most inopportune times, leading to sore noses, and fat lips.
I might lose a few feet per second using the metal loop, but I am right on top of the NFAA speed limit now with my rig, and I don't need any more speed.
Best to experiment and see what works best on your individual setup...