What I appreciated with the degree wheel on the right side was the repeatability. Once you cut the slot in the wheel, you are able to mount it back to the same position relative to crank as before.
To check crankshaft position I guess it does not matter, but to advance F3 camshaft 5 degrees, I spent quite few quality winter evenings working on it, making sure I got it right and that I have sufficient valve clearance too.