I got a pair of Danner Jackals, and have had them for 3 or 4 years, they now leak, however they've covered many a mile and have served me well. This year I bought a pair of Danner Pronghorns and have been trying to break them in. Did you guys have problems with them rubbing the back of your leg above the achiles tendon? I've put quite a few miles on them and they are still very uncomfortable to me.