I don't believe in speaking in tongues, although I was once an avid tongues speaker.  Also, I don't understand why some people have "experiences" that might appear to have some benefit at the time. 

I've never heard anyone speak in what seems to be a proper language....mostly, it was repetitive syllables.   Hence, Pentecostals can't claim to base their experiences on the Day of Pentecost, since official languages were spoken on that day. 

Also, tongues speaking is prevalent in most religions or spiritual practices.