Sorry todd, not slamming you but I see this perception put forth over and over and I've proven it is just not true, COC heads are not a "necessity". A 3 blade Muzzy went clean through my brown bear and I've had pass throughs on moose and caribou with both chisel points and expandibles the only time I haven't had pass throughs is with COC heads on mtn. goats; arrow weight, shot placement, and broadhead sharpness are way more important to penetration than head design.

The main difference you're going to see between those two heads is in keeping them sharp. If you're into honing your blades go with the G5's they are super easy to sharpen and perform really well (my girlfriend took a goat with a 100 gr. this fall at 50# draw with the G5 and anyone that's hunted them can attest to the goat being about the hardest critter to penetrate in N. America). If you're not into the sharpening routine, then get the Muzzy with replaceable blades; they work just as well and fly fine out of a well tuned bow. Neither head is going to survive an impact with heavy bone or rock to be shot another day so I wouldn't even take longevity into account.