Well, I can probably answer this one for 'ya...
I had Monster MCX-2S on my center channel. Replaced it with this cable Wayne built me.

It's an M-80 with Eichmann Bayonets & a Bybee.
It sounded a good deal cleaner. And much more realistic. But I'd expected that. I also got a lot cleaner more defined bass, and just more bass output as well.

Was a pleasant bonus. Didn't think I'd been missing so much bass, especially from a center channel...
The M-80 performed exactly like I'd read both here, and at HD. I was skeptical about getting more bass from a center channel, but it happened...
I
really need to have the same cables built for my L & R speaks (they've still got MCX-2S on them). They don't even sound like the same speaker (even though they're identical to the center) anymore, that's how much of an improvement the M-80 cable made.
I was also running Monster M351 Sub cable. Wayne built me a nice M-80 sub cable w/Silver Eichmann bullet plugs. It's very nice...
I didn't feel like my subs were putting out loose bass at all. But switching over to the M-80 cable over the Monster M351 tightened up the output, resulting in noticeably cleaner, very tight bass. I'm very happy with that upgrade.
So while I'm using M Series Monster, and not Z Series (I think the Z2 & MCX-2S are about the same thing), that should give you an idea of what you could expect from upgrading to M-80 over your current Monster stuff.