Re: The Ibanez RG1527z
I'm with aj here!
I own the edge pro 1527. The neck is fantastic. I know that this is kinda up to your personal taste (I like natural/satin necks more than the finished ones), but since you liked the 7321 neck, you're gonna love this one.
I don't know if edge zero is more stable, but I haven't read about tuning issues. If your guitar is set up correctly, I think that you're gonna be ok!
The pickups are the only "issue" IMO. I swapped mine and I think most owners have done so too. They're not bad. They're just ok (and kinda muddy to my ears). Nothing that can't be fixed though.
Try one and see for yourself!