Shipping is always gonna be outrageous...you're paying for next day air, delivery to your door, by 11am.
Even though 40lbs of rock was something like $70 shipping...that still made my order about $5.15 a pound...and locally for 40lbs of 'crap' rock, I'd be paying $5.75 a lb. so it was a no brainer.
however if I only ordered 20lbs...it wouldn't be as good a deal due to shipping still being $50 for that much rock. Hence I've picked up another 10lbs locally to save cash.
If I could do it over again I woulda ordered 60lbs from Mike in the first place.