I have a pair of meindl perfects and a pair of the denalis for whatever reason i wear a 9.5 in the perfects and a 9 in the denalis. both have well over 20 miles on them. I love the perfects but on a september elk hunt go too hot and blistered so i went to the unins. For whatever reason I seem to still have blister issues. I have never experienced this till now. For example went on a 2 mile hike today in the denalis after not wearing for awhile and blistered my heals. You guys have any tricks for preventing blisters. thnx