I have two guitars with wizard necks, a 1990 S540LTD an 1991 RG760, and haven't had any issues with either. Compared to, for example, the ESP Horizon I sold last year, both necks are extremely stable. I haven't needed to adjust the neck a single time on either Ibanez ( and I've had the S-series since 2003), while the ESP needed a truss-rod adjustment at least twice a year because of humidity and temperature change. I also remember that the RG2077XL I had a few years ago had more neck issues, despite having a 5 piece neck.
The S540 did get a small crack in the neck at the nut bolts from falling headstock first into the floor, but the crack hasn't affected neck stability or gotten bigger in the 10-ish years since it happened.
Another common thing is finish cracks at the neck-joint, but those are purely cosmetic issues (and barely noticeable)