From my experience with all 3 in 3U form, I wanna say that out of AT700, Z Force 1, and Z Force 2, the stiffest and heaviest feels like the ZF1. Its also the most unforgiving and most different of the 3. ZF 2 and AT700 are the most similar in overall feel. Note ZF 1 has the best feel being so solid that touch shots feel amazing with it. ZF 2 is the weakest of the 3 in the smash department since it hasthe least impact on improving your power more than what it is. Its loud upon smashing but the smashes are weaker. AT700 on the other hand is the most powerful hands down. Scale of 1 to 10 including .5 intervals for smashes, ZF1 is 9.5/10, ZF2 is 8.5/10, and AT700 is a 10/10. Defense wise. ZF2 is 8.5/10, AT 700 is 8/10, and ZF1 is 6.5/10. Feel wise? (for touch shots) ZF1 is 10, ZF2 is 8.5, and AT 700 is 9. Net play wise, ZF2 is 8.0, AT700 is 7.0, and ZF1 is 6.5. Forehand clears? All are a 9.5 out of 10. Backhand clears? ZF1 and AT 700 are 9.5 while ZF 2 is 8.5. Control wise? All are 9 out of 10. Ease of use? ZF2 is easiest, AT 700 is difficult, and ZF1 is most unforgiving. Shoulder and elbow problems come with using all 3, so take care of your shoulder and elbow. Hope this helps