I agree that the 920 is the best bang / buck for sure.

If you are stable at the higher speed then thats great, I really prefer stable systems to OC systems.

But because the cpu is almost never the bottleneck in wow (of course more cpu speed is good for other applications), I don't see much reason to overclock for wow. But if its stable then you have nothing to lose (ya your cpu might wear out in 5 years instead of 10 .... big deal).