Honestly, Gunn's all right. Out of all the people in DX other than HHH, Gunn was the one that should have ended up with at least one world title run but there is some sort of intangible that doesn't scream main eventer for him. It's not that he is off-putting or laclustre or anything like that; its just that I'm almost certain if I'm remembering it correctly that WWE tried pushing him as a single star at least four times in his run with the company and the crowds simply didn't care. Maybe the whole Mr. Ass gimmick kinda held him back but its what brought huim the most success. Him finding his succcess in the tag team division was the best thing for him.
Gunn's always had a great physique and even though he's older, looks in better shape than he did when he was younger. And even though Road Dogg was the son of a pro wrestler, Gunn was the better wrestler whilst Dogg had the gift of gab. Honestly, the two of them ended up being really good matches for each other. Gunn could have easily settled into a role like Iishi by being a gatekeeper to the main event scene, but settling into tag team mid-card talent at the top of is no bad trade off either. I'm no fan of DX, but can't say nothing bad about The One.