In terms of its ability to induce dread? No, not in the slightest, though this is of course an entirely subjective opinion. I was raised on horror movies; my Mother is a horror movie nut, and the one she always warned me of was "The Exorcist." As a result, the movie took on an almost mythic dimension in my mind, especially since I'd been watching films such as "IT," "Hellraiser," "The Evil Dead," "The Texas Chainsaw Massacre," "The Shining," etc since I was very, very young. When I finally got to see it at the age of eight, I found some parts of it faintly hilarious (I couldn't stop laughing at the "Jesus fuck you!" line), some parts marginally disturbing, but nothing to write home about. Overall, I was left feeling faintly disappointed.
Possession films in general don't really hold any appeal for me, especially when they have overtly Christian overtones. It always strikes me as faintly absurd that these apparently ultimate evils can't find anything better to with their time than go around possessing little girls. Wouldn't a pope or president be more appropriate?
For my money, movies such as The Shining, The Blair Witch Project, Noroi, The Wicksborough Incident etc are infinitely more sophisticated in terms of the means they employ to induce dread in the audience.