To answer the OP's question, I think it is simply "the higher the trajectory, the better the spin". So medium/high traj clubs have less spin or stopping power than high traj clubs. And also naturally the low clubs (PW, 9i ect) will have more spin than the higher clubs.
I played with the Burner Plus set upto and in the Master Tier. I did the grind to level 59 and then bought the G10's. Best decision. They are a super set of irons and I used them right up to and in the Legend Tier. Indeed, I only changed them today for Burner 2.0's after clicking over lvl 79.
I might add that those G10's of mine paid for themselves about 20 times over. Nearly every dollar I've got in "earnings" next to my name was won with those irons at Master, Tour Master, and Legend Tier.