Ok so long story short I usually run the 400, 400 hurdles, 4x200, and 4x800 and I do sometimes go down and run a leg on the 4x100 or go up to 1600/3200. I have used the nike zoom rival md line in the past and I'm looking for something more high quality. o1 option I have is to get the zoom superfly elite 2 and anytime I run the 4x8 and 1600/3200 to use my xc spikes or my old md spikes. Another option I have is the Nike zoom 400 and use my xc spikes if I run the 1600/3200. My last option is get the nike air zoom victory for the 800 up and buy a pair of zoom rival s for the 400 down. so long story short which is the best option. the superfly elite 2, zoom 400, or air zoom victory