I got some carbon express terminators for 42 a dozen at walmart about half off. Right now I am shooting 62lb but will change to 70 since I am a new shooter. I have a 28" draw length. I bought the 4560 will they be ok if i move up to 70 lb. In cabelas it says go to the next one like 6070 but in a bow shooting magazine it says 4560 will shoot to 70. Anyone know about this? Also, what size broadhead would you recommend i shoot spitfires in my old crossbow and want to stay with them. Sorry if these are dumb questions I am new to the compound bow shooting. Thanks for the help guys.