My 5x undead rogues are lvl 63. I specced shadowstep as this will allow each of my chars to be in melee range when attacking (ambush glyphs for 10 yard range help when lag keeps you out of rage). Most of the time, I don't have a problem with keeping mobs in range. Unfortunately, sometimes lag or other things (walls, my /follow macro) will make the followers face the wrong direction to attack the target, so you end up with a 1v1 scenario till you can get everyone facing the right way.

One good way without using shadowstep is to have cheapshot on the main, and run through the target (from behind for max effect on the followers). Then turn around with the main, and the followers will be behind the target exactly at melee range. When I get crits on my 3x ambush (I use 1 garrote for silence, and 1 cheapshot for stun) the target usually dies instantly.

Hope this helps