The patches will greatly improve performance (and are pretty much required since it is very buggy out of the box).
Par for the course for PC games nowadays - as well as the requirements, where I have to note that I find that over the years, they've become more and more likely to plain out lie to you. I've had games of which I hit not only the minimum but also the recommended specs lag on me with everything graphical turned down all the way to butt ugly mode.
I suppose I have finally become a console gamer without realizing it.
"Deep in the earth I faced a fight that I could never win. The blameless and the base destroyed, and all that might have been. -- GK"