I'm going to try to wade in here but I might get punched by both sides.
- I know of a toolmaker with 60+ years experience that has his vise set up with 1" long precision ground keyways that just fit the slots on his milling machine. He has pre-indicated in the precision ground jaws on the vise. Many hours went into this prep, and he has to force the vise down whenever he reinstalls it - but every time it is within one-tenth, end-to-end. Defrayed over the past 40 years since he made this setup, he has saved many hundreds of hours. The downside is that he has several scrape marks, where he accidentally marked the table while removing and installing the vise.
- On the other side, I also know of another machinist with 45+years experience that always indicates in his vise every time. He has made custom washers for the vise with flats on them that help him to get very close, usually within .001 or .002. I've watched him indicate the vise in in 10 seconds flat - to one tenth! No marks on the table, but a little extra time every install.
Who is right? well I don't know. I don't have the time to do all the work for option A, but one day I might. I have my own version of option B, but it takes me a minute or more to get it close.
To address the OP question -- I think the laser is fine for getting it to that .002 level. If that's all you care about, then just use that. If you always go for more accuracy, you have a good starting point. Everyone develops their own technique, and lives with the advantages and disadvantages of it.