Being sayed or non-sayed is wholly irrelevant here.
The criteria for marriage, from a shari'ah perspective, is that he is a Muslim, and the baseline criteria for being a Muslim is professing the shahadatayn (belief in Allah and the Prophet Muhammad).
If he is deeply committed to his spiritual leader, it may be good to make sure you are comfortable with the spiritual leader's ideas, since, in my experience, when there is a conflict between a spiritual leader and a spouse, the spiritual leader usually wins.