Difference between the 155hz, 165hz, 175hz ASUS VG27VAQ models??

[jrsaffle]

Hello.
I'm thinking about getting one of these models. I did extensive research and I've landed on this monitor because of its capabilities at 60hz, (playing on xbox now, and want something usable for new consoles in the future too.)

https://www.rtings.com/monitor/reviews/asus/tuf-vg27aq

They've shown that this is one of the lowest input lag monitors playing at native resolution @ 60hz. But I have two questions:

1.On Amazon there are 3 different versions of the same model. The only difference between them being "155hz model, 165hz model, and 175hz model." The Rtings.com review is on the 165hz model. My question is will the different models have any effect of the input lag/ response time tests shown in the Rtings.com evaluation above? I'd assume that the 175hz model probably has a faster input lag/ response time but only at the max native resolution/ refresh rate. If so which monitor would be best for playing now on 60hz xbox. And probably only 120hz on future consoles?

1.The native resolution is 1440p, but what would happen if I play at only 1080? would this be detrimental to the input lag? I'd think that it would decrease input lag since the monitor doesn't have to work as hard, but does someone actually know the correct answer?

p.s: I am aware "input lag and response time aren't the same thing"

Thank you