Mega doesn't have the hand brake. I read it's mainly a novelty and most remove it after a while.
I don't think the Felony lid will fit on an Infraction. Not 100% sure though.
They are both great. I don't think you could wrong with either. The only difference really is the Felony has different size tires on the rear vs the front. Which means the diffs are different in the rear than the front. It is def bad a$$ looking! I've got the 'Vette Felony and a mega turned 4s...