Are either of you GRT yet, signed up for a Class, or just like the product?  I was in Class 113 and signed up for Flagstaff and Phoenix, both coming up in a couple months? I ruck with my GR1 several times a week. love it.  
I'm at the tail end of recovering from a significant injury, and only just really getting back into shape.  Next year I'm doing a half Marathon, most likely several shorter races, and hopefully another Sprint triathlon.  Perhaps, after I've done those things and gotten my conditioning where it should be, I'll start training for a GRC.  My wife (the half-Iron Man finisher and multiple marathoner) wants to do it.