Not a fan of mariner seats, they have sketchy pinch points and sharp corners that were are not rounded off when lazer cut out.
Just got rid of the Mariners in our boat and went with shoxs. They are very nice and very pricy, but worth it.
Looked at the Shockwave (and rode in a boat with them as well) they were nice too, but decided to get the shoxs with more travel and zero pinch points.