The only potential issue is whether there is any unavoidable snow left by the time you get there. August is probably OK, but if it was me, I'd check right before going. I descended the MR after climbing Day Needle early last August, and it was fine. Personally, I much prefer lightweight trail runners to boots on that terrain. Yeah, I got sand in my shoes coming down the lower chute, but it was worth it. I just stopped a couple of times to empty them out. Others have made some good points about ankle support.