I am in the horizontal position camp. I prefer a jig that is center balanced. It will have at least half of the lead body in front of the jig eye. I also think jigs that do not have lead collars / barbs also tend to be more horizontal hanging. These would be what they call no collar jigs. Some of the newer wire keeper jigs also hang close to horizontal I believe. Another reason I believe in horizontal comes from my bass fishing experiences. I fish a jerkbait ( minnow imitating suspending ) plug in cold clear water conditions. One needs to be sure that this bait suspends near horizontally for it to be effective. If it gets out of wack and starts riding in a nose up position you will not get bit very much. Bass guys actually take these baits and check their suspension positions at home in kitchen sinks and adjust them to hang horizontal for this reason. I also use a #2 steel snap to allow the jig to move freely.