It seems a little silly to say "I believe these experiences exist"; it almost sounds like you're trying to imply that some greater force exists. It's reminiscent of those people that say "well, I don't believe in God, but there has to be something" as if they'd just uttered a profound statement.
I'm not implying anything greater than the evolutionary forces that gave us our other quirks. The statement "well, I don't believe in God, but there has to be something" may not be profound, but it's mostly accurate. The "something" is most likely specific neural structures that cause religious experiences in people under the right conditions.
To further clarify, I think that some religious experiences are really experienced (e.g. they are not just false memories of experiences that didn't happen) in the human brain and are not conscious self-delusion or self-deception. I think that all religious experiences have natural explanations that don't require the participation of any agent more complex than a standard human.
The Wave: In Pursuit of the Rogues, Freaks, and Giants of the Ocean is a book about very big ocean waves-- the science, the danger (mostly to ships), and the surfers.
Really big waves weren't scientifically verified until about ten years ago-- part of the problem was that even though sailors had been reporting huge waves, scientists had a theory that big waves (maybe over 80', though I don't have a sharp dividing line) required very rare conditions. Once satellite surveillance for waves was possible, it turned out that big waves were fairly common, and might explain why a ship or two per week disappears.
Russell Wynn: "The way the radar system works, the very big ones are difficult to measure," he said. When behemoth waves appeared in the satellite data, the space agencies considered these readings to be errors, and they were automatically deleted. "They give you missing value code instead, which is really annoying. We shout at them for that."
The reason I'm posting this is that I've become very skeptical about any theory which claims that something which is well-attested and physically possible is actually not happening.