Yes, I do use a hoop, though the first quilt I made was quilted without one. On that first quilt, I tried to use a hoop but it just felt awkward. And it worked out fine. I tried a hoop again on my next quilt and managed to get the hang of it; now I always use one. When the subject came up recently, I tried quilting without one again to see how it felt, and quickly went back to the hoop! lol To me, it's easier to manage what I'm working on and keep it where I want it, if it's in a hoop.
As far as the tension- I used to keep mine pretty tight but now I've loosened it way, way up. (Some people suggest imagining a cat is laying on the middle of it- it sags.)It's much easier to rock the needle up and down, and to get smaller stitches when the tension is looser.