I took one in 1992 (I think) and hated it! My instructor didn't give any guide lines! She kept saying "it's your quilt do what you like". Well I did not know what I liked. Everyone would meet after class at a local fabric store and grumble. We were so confused! I look back on my sampler quilt and am glad I had that experience because it helps me to know how to teach others to quilt. I needed to be told NOT to mix poly/cotton with cotton. I like having guide lines, and knowing what will happen if I step outside tose recommendations. That's me, though.
I later took another quilt class at a local quilt shop with our daughter and fell in love with quilting. I have loved it ever since. To date I have given 70 something quilts away and I had taken a break for a couple of years due to health and am back at it again.
I think a class is so important because you can learn tons from everyone who is learning at the same time.If you take a class and hate quilting there is hope I am proof of that!
I hope this helps you out!