This is not to tell you what to buy. Go to excalibur.com and check out the arrow performance page. I think you will find that there is not a whole heck of a difference in trajectory with in most xbow speeds. You are right the longer stroke the faster the bolt. But power is one of the lesser of the things to consider. I think that all serious hunting xbows will zip through any white tail with in sensible distances and sensible set up of bolts. Accuracy is much more important to me. Second is the amount of fussing or the amount of trouble to expect. There is big difference in weight as well (I don't care much about weight myself). Some people care how narrow the limbs are (I don't). Not going to tell you what I shoot. Check out the thread "what xbow do you shoot" to see how happy everyone is with their stuff. The only important thing is that you are happy. After all isn't it all about you? LOL