For one, shopping for clubs by stiff graphite vs regular steel isn't a comparison. If you are fitted for a stiff flex then use a stiff flex but don't let people talk you into adjusting your flex based on material, make sense?
Graphite offers great damping properties especially for people suffering from tendonitis and such. A past study showed that golfers are still playing a shaft too stiff and heavy for them (which could be another topic)
Another great thing about graphite is that the quality has become far superior in recent years (hence the higher cost) and allows the manufactures the ability to manipulate weight, balance points, kick points, tip sections, etc far more than with steel. With steel you can control a lot of that with the steps in the shaft however not as easily as with graphite, creating a truer matched set.
I don't suffer from tendonitis but I've been curious about graphite shafts in irons so I've built several demo clubs (and a complete set) to see how graphite shafts compare to my steel shafts and in many head-to-head tests both on the course and with a launch monitor a
set regarless of material provided great results.
Like many products there is poor, good and great quality. Graphite will cost more than steel when matched with equal quality.
Common myths associated with graphite irons shafts
Graphite shafts are for old people - Not True, as mentioned above graphite shafts in irons offer many advantages when compared to steel
All graphite iron shafts are cheap quality - Not True, like steel shafts, they are offered in a wide array of quality. This statement came about because golf club manufacturers will use cheaper quality shafts inorder to save cost and profit margins
Graphite shafts are not as accurate as irons - Not True, if you were properly fitted this wouldn't be an issue.