I do not own nor have ever used either detector but I am considering both.  Other than price I know nothing.  Read a few older posts & reviews on the SDC 2300, it may be a better fit for the steep brush covered ravines of the Sierra west slopes along with the cracks and crevices in the drainages. Currently use a White TDI SL with a 10x5 folded mono coil. I have hear that the SDC 2300  8” mono coil is hot around the edges. I like the specs on the new Axiom overall but for me the current coil