The term "Demon-centric" would mostly have a negative impact to the audience while "Holy Spirit" seems to be Sweet and Beautiful in itself whether one experiences it or not. However, the practical reality of being Pentecostal is "Experiencing the Spirit (Holy Spirit) and not Otherwise." Experiencing demonic activities would not determine one's Spirit of Pentecostalism. Yes.
So, in Pentecostalism, I would classify a few categories:
1. One who Thinks Its Reasonable to believe.
2. One who Believes in It.
3. One who Accepts it.
4. One who Experiences, Practices, Lives with.
So, nowadays many who claim Pentecostals are no longer Pentecostal while some others are Experiencing it though they would never label with it.
The presence of Demonic belief is not a good measurement to proof that there is The Spirit around. Well, many would sidetracked on their Journey of Faith. After all, Pentecostalism is a Movement as in Pentecostalization (Globalization) rather than a doctrine or dogma.
(Its a personal thought though).