well, this can be a tough one, 'cause many CZ users have a real hard time just setting aside everything they have learned about that detector & starting over with a 100% different approach. I would say yes the Edge can keep up with a CZ, ONCE MASTERED.....& yes the Edge is lighter/better balanced, much easier to ground balance, great in trash, etc. Again, just be certain your wife is willing to really want to learn a new detector. Some find the learning stages interesting & fun, many others give up quickly & go back to their old unit. The Edge is number driven (rather than those icon squares), and the pinponting is different. It can be argued that both those things make the ID-Edge more accurate. The 4 tones are about the same, & both can notch out similar trash items.....
hope that helped?
Bill