Just drove the car home from the tire store with the monoblock versions on and it felt more lively so I knew I'd dropped unsprung weight. After taking out the weights of all of the wheels on my digital scale, here is where they ended up vs. the factory SRT8 wheels:
New 20X9.5 fronts 28.5 lbs. each
New 20X10.5 rears 26.7 lbs. each
Factory 2013 Charger SRT8 20X9 wheel on the same scale: 33.1 lbs.!!!
I went from 132.4 lbs for the set down to 110.4 lbs. The 22 lb. drop in unsprung weight is evident as soon as you drive the car. I'm pretty stoked.