Maybe "lied" was too strong a word. Sorry. I am still a big fan of Magpul. This minor irk aside, I would buy them again.
More accurately: I tried 2 different A2 front sight tools (Tapco and Leapers). Neither fit my MBUS. Both misfit my MBUS in the same way. Both fit my son's S&W M&P perfectly.
The MBUS seems to have the proper spacing of holes but the holes appear too narrow. The pins on the tool will not fit into the holes. I guess I could file the pins to fit the holes.
No big deal. The front sight is now spot-on at 50 yards. I am good to go.