One of the local stores has some uncut Carbon Express Terminator shafts on sale for a great price. I draw 29", but generally use 28" arrows because of the WB rest set back on the riser. For the spine to be right on these Terminator shafts, which are one size stiffer than I normally use, they would need to be no shorter than 30". Is there any downside to running a longer arrow than really needed?