David,
Either one will work fine. The 8,000 rpm will work better, but not enough to make a difference to most people. I bought an 8,000 rpm Apple Pro saw with the dust collector because I wanted the best machine to cut the arrows and a way to keep the carbon fibers out of my lungs. There really was no reason to get a saw that can do the heavy duty work of a large archery shop when I don't cut that many shafts. A $65 saw would have done what I needed just fine, but instead I ended up spending $200. The way I figured it, the extra $135 was only about what I would pay for a dozen nice custom arrows. I guess I will be cutting shafts for all my buddies too. There is no way I could ever wear out my Apple saw. I really don't think I will ever save money cutting and fletching my own arrows, but at least I can get the arrows tuned the way I like them.
Allan