Just strung my new YT Prestiges and no problems at all with head distortion. I even compared the first racquet I strung with another one that was still unstrungs, and no distortion at all.
I have a Gamma X6-FC, 6 point mounting.
I also already strung a YT prestige Mid and another YT Prestige MP and no problems as well.
3 Head IG Radical MP - Hyperion 1.18 x MSV Focus Hex 1.10 @ 45 / 12g on handle
Gamma X6-FC // Member of 18x20 club