I loved the Lyman 139, demoed it for a few sets, almost bought one, then I rode the LF witness 140.... and that's all she wrote. This was back in 09-10? I have been on a witness ever since. Haven't ridden the witness grind yet, but that is all they offer now for 2015. I hear it feels the same, maybe a little bit more loose than the traditional witness, but I do not know yet. I am still rocking my 2013 witness. The two were similar in speed, and without the center fin, similar on how loose they felt. The only thing I felt that was noticeable between the two was the witness has more pop. Both boards were excellent... and now both boards are discontinued
But if you can get your hands on a 2013 witness, I d would give it a try.