Mine's a toss up between QHs and Arabs. I've owned/been exposed to QHs all my life, so it's hard to get past the bias towards them. I'd always been told that "Arabs are crazy" so I'd avoided them until one was given to me, and while I agree that he was much more spirited than any QH I had worked with, he definitely wasn't crazy.
I love the look of a QH, but also think Arabs are beautiful. I also love how Arabs seem to let you know that they love you to pieces. When I'm away from my horses for extended periods of time, my QH is mad at me and lets me know it. My Arab is like, "I LOVE you I missed you where WERE you when can we go out and plaaaay?" While the QH is more like, "I could care less that you're here" and then when I walk away he's like, "where are you going, you aren't leaving, are you?" LOL