I bought this primarily for a guide for my circular saw. The I-beam has no machined edges but is really straight. Any mistake in my cuts will not deviate from the level. I checked the level for accuracy and couldn't find any errors either way. I was expecting some kind of error with at least one given how cheap it was, but was pleasantly surprised. Protective end caps are just plastic instead of rubber like a typical box beam, and box beams are generally stronger. Also, the height is 96 inches including end caps. I was expecting the I-beam to be about 1/4 inch longer, but that doesn't bother me. In general I am satisfied. If I take care of it, I expect it to last me a lifetime.