FYI - and just a suggestion as the B-head thing gets hammered here and there are SOO many great ones that it come down to which brings you the most confidence but I believe a solid COC head is better than a multi piece product. Again, just an opinion. If 3 blades is your pref think about Wensel Woodsmans as they can be pretty light with light adapters and even 20-50 grains is so small it will be undetectable for all but the most proficient target archers(think Olympics) IMO.
With hunting weight bows and arrow set up at hunting ranges the difference will be microns.
That said, my set up lately is 45@25 and I shoot AD Trad Lites cut to 27" with WW on the business end. Some have steel adapters, others aluminum - all shoot to the same spot at hunting ranges and these shafts are super forgiving of bow weights. I shoot the same set up from 45-65lbs with equal results in arrow flight.
Again, just another hunters opinion so take it with a grain o' salt but I would be less concerned with the exact grain weight of your broadheads and more concerned with arrow flight. It just is not that important and you will be continually chasing the weight as you sharpen a few grains off your chosen head - and for not good reason.