Most of those are inherently a waste of money unless you ALWAYS use
the exact same length of drill bit in all the bits you have/use. If
the length differs, then you gotta re-adjust/re-calibrate the laser

Do these laser things project from one point or two?

If I were designing a laser marker I'd project two lines from two
points behind the bit, one on each side, to intersect in a line - that
would mark the correct spot regardless of table height or bit length.