Accuracy, Accuracy, Accuracy....head and shoulders above the rest. You can have the fastest, or the most durable, or the heaviest arrow on the block with the best broadhead ever made...if you don't hit the spot you need to, they are not going to do you much good.
After that is a blend of good speed (but not neccessarily blinding) and penetration. However the latter point is moot with the majority of todays equipment, and a good broadhead.
I don't think it's a secret here that I prefer ACC's above all else for their excellent real world tolerances (not "spec sheet" tolerances). However, I'm always searching for someting as good or better in the all-carbon lineup.
Recently I purchased half a dozen IC type arrows of a brand that shall remain nameless. I've had fairly good luck with their premium shafts, as well as a Pro-shop only model that is very heavy. In looking for a somewhat faster arrow at slightly less cost than the premium versions, so I picked up their most popular shaft (run about 70 to 80 bucks a dozen). For the life of me I could not get them to group out of 2 different bows. Weights were decent, no contact, no tuning issues. Frustrated I gave up. I went to my arrow box and picked out 2 ACC 3-39 shafts, fletched them up, went outside and stacked them on top of each other at 35 yards without even papering them or tuning them to bow.
I pay about $3.50 more per arrow per ACC's than those mid-priced shafts, and about $2 more per arrow than the premium shafts. For that extra money I'm getting phenomenally better spine consistency, unequaled weight tolerances, more than adequate and more importantly CONSISTENT straightness, and ultimately extreme accuracy. In addition, for the IC carbons I would have to add about another dollar per arrow to get the same nock end durability as ACC's(by utilizing a uni-bushing and G-nock) because the IC carbons are very suceptible to nock end cracks and resultant spine loss from hard nock end impacts.
You can take a $200 bow and get it to shoot great with high grade shafts.
However, even with a $1000 bow, you can't shoot very accurately with junk shafts.
Next to the archer himself, the arrow is the most critical thing for accuracy.
As I always say, look at the big competitive shoots...you basically see 2 different types of arrows..Aluminum XX, and A/C in it's various forms...there's a reason for that.
JeffB