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TX, relax brother,
IMO you really can't go wrong with either. I would call both comapnies if you haven't already and speak to them about what your plans are for the car and go from there. They will give you good advice.
I have the G5X3 on a 112 and I love it. The idle is pretty rough but thats what I like. Makes a pretty good torque curve too, my tuner compared my curve to their H/C setup, they make a little more peak power but I have better low end torque. They also have different heads, I have stock heads ported and polished and milled. Good luck with your choice I dont think you could go wrong with either of those.