The older version Carbon Express Heritage 90 have a spine of .530,the newer Heritage 90 have a spine of .588.A 2016 has a spine close to the older 90's,but I find you can't compare spines of carbon arrows and aluminum arrows.They react and recover differently,plus a 2016 is a 5/16" diameter and the Heritage 90 is a 9/32" diameter shaft.Why do you need them cut to 27"? For me I never just cut an arrow without shooting and tuning it to my bow.A 500 Axis would be close,but then again it is a smaller diameter then the Heritage 90 and will require retuning.A 2016 is the closet in spine rating but you have different diameters and a different arrow material.