Some of us prefer Wagner and some prefer Griswold. I think the older Wagner pieces are just as nice as the Griswolds. The important thing is that YOU like it. I have pieces made by Wagner and Griswold. I am not as fussy about my users, so as long as it is well cast, I don't care who made it.
As far as seasoning this beast, after it is cleaned, I would warm it on the stove, coat it with Crisco, front and back, then wipe all the Crisco off. It will leave a fine coating, and then you can use it. It will season more with use.