It all depends on my level or the strike at hand, say its archon priest, you got 2 areas with a nice amount of enemies that you don't need to kill, at a low level ill kill them and get that extra exp, on my 30, i just run, or if i have a lower level, 24 or so on the 24 strikes ill kill so they can make it through easier, but there is a lot of factors that will make me choose a side, if i'm playing with all 30's i just run, because they should have no problem getting through if they want to kill everything, where lower levels may have trouble running. personally i like to run, kill the boss, next strike, imo there is a time and place for collecting materials and its not during a strike, and if im running ahead and your a completionist, dont quit, just kill what you want, and by the time you get to the end, the boss should be dead, and rewards received! because runners obviously have no problem doing all the things they need to on there own, i know i don't. no matter the level.