Just remember that these 5ms and 1ms response times are best case scenarios, from gray to gray. In high contrast color changes, it can be as much as 6 times that, which is longer than the refresh rate of the monitor when you are at 5ms as the best case scenario. That means that under motion, IPS panels suffer with motion blur. You should also find that tearing is far less noticeable on a 120hz or higher monitor as well as feel more responsive.
For gaming, I'd rather have a 120+hz monitor. For the desktop, the IPS would win, though they do not have better black levels, they have worse black levels. That is not their strong suit.