I think what I was driving at is Versalab projector box is purpose built with marked target and fine projection, with any other laser a similar box would likely be needed as the width of the laser beam (from a device like that Bosch) is quite large by comparison and accurate assessment would be nearly impossible. A good laser leveling tool for, construction work, costs hundreds of dollars, and dollars translate into a higher quality laser beam with tighter specs. Not knowing all the facts about both I still would say the savings are questionable given the overall satisfaction with Versalab performance and the rather unknown outcome of modifying a tool not originally intended to do the task.

This is not the same as saying the Bosch cannot be used to make a useful enlarger aligner, which I'm sure it can be, but how would you test it?

At the end of the day, making a negative of a flat test target with fine corner detail and checking the print might do. In my case, I've always been satisfied with the use of grain focuser (like Omega Peak) to check for alignment (grain is sharp around the negative regardless of its detail, so any negative can be used), as this is as far as I felt I needed to take it.