I bought 6' 10" Plasmid during the summer doldrums. I was so-so with it in smaller waves, the wave cheat was exciting but once that wears off, it felt stiff, and strongly believed it was a potential YOLO mistake. Until this weekend, in shoulder to overhead plus, with a bit hesitation, I decided to surf it. The board worked well, get in early, lots of speed and hold, and maneuvers well for its size. As
@oeste858 said, you can surf it off the tail and push the board. It handled some of the bigger waves with no issue, big drawn out bottom turns on some of them. Board didn't feel stiff in bigger waves. I started with the Asher Pacey 5.79" owing to the board size, and they were too much fin, the NVS uprights freed the board up and feels right. Not sure if it is my exhaustion speaking owing to the long paddles back offshore, I thought it paddled okay, but caught waves very well.
I was definitely on the right board, as the shortboards were getting destroyed with the drops, I am usually one of these guys trying to catch these waves on a shortboard (everyone was asking what I was on -haha) and the long boarders were positioned too far on the outside or couldn't make it out.
I also purchased 6' 7" Darkness when I was in the Album store about a month later this summer and chatting with them about my Plasmid thoughts. I am still figuring the Darkness out - it is pretty flat relatively to the Plasmid, not sure how it would have went the last 2 days. I am not much of midlength surfer, but today could have changed that or at least for the big waves.