Yes, I believe that personal experiences are reasonable evidence and that they are a valid basis for personal religious beliefs. The key word is personal. I acknowledge that they their use as scientific proof or in a formal debate is problematic, if not impossible. Source and cause are always subject to opinion and it is true that the mind can be tricked. It can be tricked into believing something that is false and it can also be tricked into disbelieving something that is true. This makes it difficult to absolutely accept or refute the religious experiences of others.
We make decisions and form opinions based upon a number of things. We consider evidence of many different types, and personal experiences always factor into the belief system which we adopt. This isn't limited to religion, we all take personal experiences into account when making decisions. It's also acceptable to relate these experiences to others and to offer them as a basis for our belief. As a Christian I might use personal experiences to explain the reason for my faith. I also have to accept the fact that the person hearing my evidence is not constrained to accept it as valid.
If I might offer an example; my father died of emphysema. It is my belief that this resulted from years of smoking cigarettes. My belief in this is based in part upon personal experience (observations) and in part upon scientific evidence. Both represent evidence that I considered in forming my opinion. If I were speaking to a group of teenagers on the subject I would be inclined to focus on the scientific evidence, but I would also offer the evidence of personal experience as the reason for my passion. It would be up to the teenagers to decide the merit of my evidence.
Personally experience is jus that, personal. While I believe it can be valid evidence for a person. It cannot be valid evidence in any sort of arguement. A supernatural experience is almost always some form of a hallucination, or highly improbable chance, or even just a lack of understanding of the natural world
IF I do not know what cause your unexplained experience, that does NOT mean that your god is any more real. In fact, I would argue it's disproof of religion. Why would a god, who can speak to everyone at once and let humanity know what the true religion is, handpick a select group of people?
I know it is a tricky issue as no one can can experience another mans life but I still think there is enough of a rational explanation to discount personal experience as valid evidence. I dont doubt that people had some truly incredible experiences but I am also aware of the human minds ability to be decieved. By outward sources an by its own machinations. People can make themselves believe anything they want too and with the incredible diversity people face in their lives all sorts of bizarre things are likely to happen.
While I am skeptical of personal experience on the face of it I think that it is further discounted by other issues such as a lack of evidence of personal experience being super natural itself. It is also the abundance of positive evidence for personal experience being phoney in the vast majority of cases. Like people who speak in tongues when they have the holy spirit in them and stuff like that. In summary I think personal experience is a misinterpretation of the world around them.