The first time I attended a charismatic church some 15+ years ago, the thing I liked the most was the praise & worship. It was--well--alive! I could understand it and enjoy it. I could close my eyes, raise my hands if I wanted to, and not worry about what anyone else in the room was doing. For me, that was the very definition of freedom. I loved the worship, and even when I was unfamiliar and uncomfortable with other aspects of Pentecostalism, it was the worship that kept me coming back.
I guess I ought to make a distinction between the worship and the music. The worship was great. The music was OK. The musicians were (by and large) not professionals, just folks who loved God and (kinda) knew how to play a few chords. They hit wrong notes sometimes. They tripped over the words. They couldn't always stay on pitch and the harmonies were often less than harmonious. The songs themselves were simple... and looking back, some of them were just kinda silly or even downright embarrassing.
The music has come a long way since the 80s. Most churches today have paid worship leaders who are accomplished musicians. Larger churches even pay other members of the band. If you visit a contemporary-style American "mega church" today, you're guaranteed a quality show complete with all the staging, lighting and multimedia that you'd find at a modest concert.
In more recent years, I wound up attending a pentecostal mega church. It was a very good church--no scandals, no major conflicts or controversies, respected in the community, etc. Everything they did was very high quality, including the music. It should have been everything I wanted and more, but before long I found myself wishing I could go back to the worship I had known in the early 90s. Something was missing. I couldn't pinpoint what it was, but I was certain that I'd know it when I found it.
I started visiting other churches. I went to special services and conferences. I even enrolled in a worship school! I found a place where the services were nearly identical to the style and atmosphere I had loved so much in the 90s... but even though I had found exactly what I was looking for, it was a short lived and empty victory. Maybe time had skewed my memories of "the good old days." Maybe I had grown older and less open-minded. I just couldn't stomach some of the stuff I was hearing. It was easy to avoid asking the tough questions when I was in a less "extreme" pentecostal church, but now I was being confronted with large doses of things I had never been entirely comfortable with in the first place.