Those three words are what I do (in that order) when I think about Peter von Gomm and Jack Merluzzi's performances as X and Zero (respectively).
But did you know that they also voiced another famous videogame duo? In KOF XII von Gomm voices Kyo, and Merluzzi voices Iori.
So far, all of the performances I've heard of von Gomm's (which would be 3 to be exact) have been horrible, and rather painful to listen to. His characters sound... forced. Or dead. Both work. Have you ever faked enthusiasm? That's what he sounds like. Like he's bored. I'd like to say he's overacting/overcompensating, but his acting is waaaaay too dry for that to be the case. To make matters worse, his voice doesn't match any of his characters. X? Not really. Kyo? Not even close. Frank West? Eh. To be honest, Frank's his only performance that I can tolerate, but it still sounds off. The icing on the cake, is that his vocal performances (specifically his X) grate on me so bad that they're ingrained in my head. His performances serve as an example of how I DON'T want to sound when it's my turn.
Merluzzi is a little better. He suffers from "non-fitting voice" syndrome as well with some of his characters, but his voice is much more pleasant to listen to. Out of the 5 games I've played that he's had roles in, I can only remember what he sounded like in 3 of them. Granted, his performances were nothing spectacular, but they weren't too bad, except for Zero's. Zero was his worst. For Zero, he decided to go a little lower than usual, which was an odd move considering the voices he did for Shiraz (in Musashiden II) and Iori (KOF XII) didn't sound as bad. Personally, I liked the sound of his Shiraz. I think that was the only character out these three that his voice fit. I think Merluzzi's a victim of "non-fitting voice" syndrome. Kind of like Leene Hardt (Axl and Musashi's actors from X7 and Musashiden II respectively).