50 is pretty average. I'd even consider 75 pretty average and 100 is not rare. I like 50 ED but have gone up to 100. Not a big diff between 75 and 100mg. I'd say between 50-75 is best.
I Usually start @ 25mg's and bump it upi by 25mg's till I reach 100mgs, then taper it back down! Seems to be most effective way for me! No need to go over 100mgs IMO and 25mgs is usually a little too low!