I'll start off by saying I'm an avid user of JPW Industries (owner of Wilton, Jet, Powermatic and maybe others) products. I have several Jet products and a few Wilton vises and hammers. So I'm fairly confident in the fact that Wilton makes some of the finest bench vises around, but they missed the mark big time with this. I'm giving it 3 stars because it is fairly beefy and does work, but is definitely not for precise, milling work. I set this up on my Jet mill and again, it's stout, but as I was trying to tram it in with a Starrett test indicator, the best I could get was 2 or 3 thou of fluctuation. I could literally zero it on one side, run it across, and it would drop 2 or 3 thou, and then come within a thou of zero again at the other side. Now, that will work for general work where stuff isn't exact but, if you need closer than that, as far as the mill jaws being flat, just get a Kurt. I was going to pick up the Kurt style Wilton as well, but this honestly scared me away from doing that. The machining is not very clean on the jaws either. This has got to be made offshores, and is priced about 150 bucks too much. My friends Grizzly brand Kurt style vise is more accurate and over 100 bucks less.