Though I have never been a Pentecostal, I remember well the frequent stories I heard of this religious movement while going from house-to-house in the past. I wonder if you guys heard similar stories.
One story I heard a few times was about the confession of some males going to Pentecostal churches to peek at girls throwing themselves all over the floor in epileptic movements, and some mention the word "panties" being exposed as an attraction to them. When I invited them to the Kingdom Hall, they said our meetings were too mild, nothing "provocative" to entice them to our meetings. No wonder they attract many converts. I guess Christ was not their main motive.
Also, one frequent story I heard from Pentecostals was that they had a lot gatherings, and women were the ones who supported the gatherings. Their husbands stayed home, and many pastors could not resist having all those lovely ladies going to church alone, and some ended up going to bed with them. A lot of marriages were broken this way.
Another thing I experienced more than a few times. Some Pentecostals were aggresive toward the Witnesses. Some have thrown their dogs at JW's at their door. Others have dumped a pail of water right on the JW's. And so on. Not to mention, that when it comes to bible discussion, they easily become fired up, some threatening.
Through the years, I met some really nice Pentecostals too, and some have surprised me with unusual zeal sorely lacking in the JW's org. Some seem to take their religious fervor seriously and pray sincerely. The apparent faith of some Pentecostals is amazing, compared with the cold, ritualistic approach of many Witnesses. But overall, the good impressions I have had with Pentecostals are outdone by the bad taste left over by my sour encounters with them.