Degree wheels can be so much farther off than the factory machined pulley it's not even funny. Not to mention the fact that you can't really use one with the engine in the car, and once you've set it up you have to determine the error factor anyways...

For any basic repair or setup purposes, the timing marks on the cam and crank pulleys are just fine. The main reason for using a degree wheel anyways is to profile camshaft lift and duration versus crank angle anyways.