You should not lose to any rogue without COS for starters. Against COS, whatever opener they use, blink and summon pet, now he is in your face with COS, ice block right away do not take any hits. Now you took relatively little damage about cheap wow gold, he will probably kill the pet, but he only has one blind and one vanish left. It is simply not enough to kill you without prep for a second set of cool downs if you play defensively. Against this strategy I use vanish and blind to force ice block, and save sprint COS for after the ice block to get cheap wow gold.
Against a top 41 frost mages I sometimes do not have enough damage to kill him, although prep would have sealed the win (he would be at very low health but I would be out of cool downs without prep), playing one set vs one set, he can give me trouble. The first mistake mages with ice block should fix is that the second a rogue is in your face with COS and blink is on a cool down, ice block right away about cheap wow gold! Do not take any hits! Treat COS the same as kidney shot and you will at least make me use more cool downs.
This requires 5NS for 120 energy, but it one shots the paladin if he does not trinket it. The damage of mutilate makes it more enjoyable to play, especially if you also PVE. I still believe COS is the stronger PVP build in every way to get cheap wow gold, but I can definitely see why people stick with mutilate if they prefer that style of play to get cheap wow gold.
I will probably try to find a mutilate rogue (hint: sunken or yume?) and make a 2v5 arena movie, so you can see both builds in action. They are literally opposite of the spectrum.