I did the same thing as kaib and leveled up to 375 tailoring two times, just to get the best gear for my spec at that time. Its pricy but worth it. The gear you get is just too good to not have atm.
Rickert
Can you still use the mooncloth or shadowcloth stuff if you no longer have that specialization?
With my priest I had about 5700hp unbuffed and there was no fight I had trouble surviving.
The only thing I could die from was arcane missiles from aran, but just pom yourself and you'll be fine.
Primal mooncloth is definately worth it.