The second you switch to a carbon arrow, you pick up a minimum of 20fps. They are either straight or broke. I've never had an issue, nor do I know anyone personally that has. From the OP, it can happen, but so can anything else. I had a brand new AR-34 upper limb crack and just about com apart.(Could have killed me) Turns out it was a design flaw that caused the problem that no one else in the world had had, yet they already had new limbs ready that fixed the problem.
But anyway, carbon arrows aren't to be feared. Things break and can go wrong with anything. I'll take the 20-30fps and the security that my arrows are straight.