Well, QS wins in terms of length, speed, and cost. And it has knockdown. And yet, it has felt weird to me when using it in terms of getting a feel for my reach with it.
Personally, I like the spear better for its easy pierce damage.
However, I hate fighting against either of them. So spammy, but I hate fighting the spear more-so if that tells you anything. (Fear the spear).