The build quality is good, the welds are good but the fit is a bit off. I had to grind quite a bit off the mounting bosses to get them to fit. This was not big deal for me, just 2 minutes of work with with the angle grinder. The upside is they are huge! And my bench testing suggested they take significantly longer to heat soak than Greddy and flow just as well. I did my heat soak testing with NO flow across the core.