Honestly, I've never tried it. My first yarn purchase was from an LYS -- I felt so overwhelmed and intimidated when I went in there that I didn't do much exploring. I asked the nice lady to suggest something and ended up with a wool/acrylic blend -- it was cheap and I liked the color. I came online to look for videos because the book I was trying to learn from wasn't very good, and I found this place. I learned about KP and ordered some WOTA which I liked much better because it was softer and a lot springier, which made it much easier to work with. (I also really liked the price!)
Anyway, as I continued to read through past forum threads, I quickly learned that that Red Heart and acrylics in general, were not very popular. One "exception" that a few people mentioned was Caron Simply Soft, so I went to Joann's and bought some. Unfortunately, I didn't care for it much because it wasn't very stretchy, which made it a lot harder to knit with, in comparison to WOTA. It also felt a little weird on my hands... I can't explain it.
I've never liked wearing wools very much but I really prefer knitting with them -- lately I've been favoring superwash yarns for practicality -- and especially merinos, for obvious reasons. Cotton just doesn't do it for me -- at least I haven't found one that does. People keep talking about Plymouth Encore as a nice blend so I've been meaning to try it, but haven't gotten around to it yet.