The biggest difference between the 2 sets is in the 3,4 and 5 irons. They increased the stopping power of these which is huge for Legend approaches. They also evened out the club gaps to 15. That made the set PW 120 and you should watch BolloxinBruges' RG video if you want to see it work. It punches 103 so you actually get 2 wedges there.
If you want to play with the best stuff, get these. They are worth it just for what the longer irons do.