From what I've been able to pick up, I'm under the impression that the GLMs are very similar in performance to the EMIs, Dana, ... but lack the "fit and finish". Don't know where the Kodiak falls in line, but they are very popular around here and readily available, hence they're on the list. One of my goals in posting here was to learn a bit more about exhaust manifolds and get some opinions on biggest bang-for-the-buck...