If everything was checked out that engine should be fine. I can honestly say every part in the one I went thru was good quality for its intended use, just not hand fit. I would not worry about what you have, use a rev limiter, do not get it to hot, and enjoy it. FWIW I never trust machine work, always measure, and never install out of the box heads. I at least take them apart and look, and usually have the guides and valve job tuned up, it does not cost that much.