Running the Mesa-Phoenix marathon next weekend! Looking forward to it! Re shoes, i run almost exclusively in light-weight racing flats, and I'm fairly convinced they reduce muscular injuries for me. Big, cushioned shoes haven't been shown to effectively reduce stress on the body, and some recent work has indicated that they may, in fact, increase the impact of running. I think the most important thing is to just run in a shoe that's comfortable for you. I will say that I rarely keep shoes past 400 miles any more. My toes blow out big holes in the uppers of most shoes by 350-400 miles, and it's rare that the soles are in good shape past that point anyway. Fortunately, my favorite training shoes of late have been Nike Streaks and Speed Rivals, and both are easy to get for quite cheap.