Be careful with 'advertised' response times. Certain companies will measure it differently in order to provide a flattering number. And actual performance varies per monitor anyways.
Either way, it just depends on your sensitivity to motion blur(usually called ghosting here). It doesn't really bother me much if I'm playing at 60fps. Could be better, but I'm not willing to forego the advantages of my IPS for it. I know there's a couple high end IPS monitors that have pretty respectable response times, but they're out of my price range.
So there's no real way for us to give you an answer. It is important to some people, not as much to others.