Angled laser mount, good idea or bad?

I saw this on another forum and thought it would be perfect because then my spindle and laser would both share the same zero. Is there any drawback to doing something like this?

I’m not a laser person by any means, but even as a zeroing tool, would you still not have xx amount of error? (due to the ellipse)

I thought that might be a possibility too but figured it was worth asking since I have to make a new mount soon