At 60lbs with that bow, get the 250's and cut to 30". and really for optimal spine, I suggest raising wieght to 63-65lbs.

If you want to move up to 70lb, cut the arrow to 28" and you are good to go. This is all with 100gr tip.

Shorter the arrow, the stiffer reaction, need more draw weight, longer the arrow weaker reaction, need less draw wieght.

With your 27" draw, 350's are too stiff in either case.