If I had a Spyder 30 I would keep what I had. To me it would not be enough of an improvement to justify. From the numbers I've seen the RKT cams are slightly faster, but the z5 is supposed to be smoother. It all boils down to do you want to spend $1400 for a carbon bow. I did see a video of a guy shooting a 3 shot group at 80 yards with the new Carbon Spyder and it was an awesome group. I'm sure it would be an awesome bow, but again for me it would not be worth an upgrade, but I'm not the one that matters. Only you can decide this.