On the CycleOps Fluid2, the power curve depends on the kind of rear tire you are using and how tightly you clamp down on it. You also need to let the unit warm up for 10-15 minutes first.
I have a PowerTap and here are my own anecdotal measurements with the CycleOps Fluid 2. I'm using a Michelin Carbon tire and I always tighten it down to spec (which for the Fluid2 is 2-and-a-half turns after the clamp touches the tire).
14 mph = 130 watts
15 mph = 145 watts
16 mph = 160 watts
17 mph = 185 watts
18 mph = 210 watts
19 mph = 235 watts
20 mph = 265 watts
21 mph = 295 watts
28 mph = 600 watts
30 mph = 700 watts
These are rough ballpark estimates and, again, these are based on tightening the clamp 2.5 full turns from the tire-touch point on Michelin Carbon tires.
--Steve