According to the cycleops website, you can upgrade a cyclops trainer's resistance unit:
Can I upgrade my trainer?
Yes. You can purchase new resistance units if your original trainer was manufactured after 1999. Please call your local dealer or our customer service department for details. 1-800-783-7257.
I picked up a mag trainer on ebay for $50 shipped, and found it to be quite loud. I wondered if anyone had gone through their upgrade deal and knew how much it is. I'm looking to upgrade to either a Fluid2 unit or a Magneto unit. Thanks