I have seen many Jizohs, some better than others. His ratings say he is best in arena both off and def. Not much else. Depends also how far you are willing to go with masteries and artifacts and books (12).
I think most give up on him after awhile when they see all the other champs that are out there.
There are certainly worse champions, but there are also many better ones and it sounds like the OP was going for their first 6*, so their starter would be a better choice than Jizoh.
I have also the impression that Jizoh would be the first 6* champion for the OP. I would recommend to 6* the starter not Jizoh.