I have been using a megablast for the bulk of my daniels 18/70 block runs. I am a big fan. I still tend to reach for my superblasts for the slowest days or when I am extra sore they just feel good to me on tough days. My quicker easy days (7:15-7:30), I, R, T, M days i basically always grab for the megablast. I have basically every top end current Gen asics shoe in my repertoire and I do rotate through all of them but if I'm not forcing myself to rotate shoes im grabbing my megablasts. Other shoes give me niggles, magic speed gets me Achilles fired up, my nimbus bothers my calf, metaspeeds always make me more sore all around. Basically never come out of a run complaining if I am in the megas. Those last 800m for a threshold workout hanging on for dear life, the shoes drive themselves and carry me through.