Just picked up Halo Infinite a few days ago, and been playing nothing but it lately. IMO it's a very good game, and while it is a bit tricky getting graphics settings adjusted without problems, after checking out Digital Foundry's optimized graphics settings guide, and discovering some things on my own, I now have it dialed in with higher settings than I thought I'd be able to use, and the performance is very good.
I had a lot of flicker when first applying the settings, and flicker and stutter at end game after finishing the story, but I think I have it figured out now. I discovered the flicker only happens when moving or looking around, so I tried dropping mouse polling rate from 1000 to 500. Upon quitting game and rebooting, I also noticed Windows Defender, after blocking two harmless apps previously, had now quarantined a harmless app. I figured the latter may have caused the stutter as it said it had just scanned 5 times.
I am now back to playing flicker and stutter free. It's a great game IMO, easily the best Halo game I've ever played, and I've played them all. It can be a bit nerve racking at times trying to drive a land vehicle on the very rugged terrain, which leads to MANY impassable terrain features or chasms, but exploring on foot via the Grappleshot makes all the woes go away. Your squad even often manages to catch up on foot if you just stop to deal with stray enemies or scavenge a bit too, so it doesn't have a huge impact on gameplay.
This time I waited until I played all the way through the campaign, and sorted out any graphics and performance issues before weighing in regarding a review, but I feel this game is at least 8.5/10 worthy, and that would be a solid 9/10 were it patched a bit better. The main problems I had, were flickering, cutscenes going black screen, some flicker and stutter at game end after finishing the campaign, and a bit of lag from frame drops when cruising fast through a wetland area in the Ghost. I believe the flicker and black screen in cutscenes was due to the high mouse polling rate I was using, as I noticed the flicker only happened when moving or looking around, and the cutscenes came back from black screen if I just moved the mouse.
Since lowering the polling rate to 500, I've had no flicker. The stutter I had (in just one brief end game session mind you) I believe was caused by Windows Defender having done 5 scans and quarantined a harmless app (Desktop Reminder 2). Even the lag when cruising over that one specific wetland area (near where the Pelican crashes), went away after I dispatched the enemies scattered there. When I went back to that spot after taking out the 3 big guns, the 2-boss fight there was not laggy at all. I'm not saying the game doesn't need patching, clearly it does, but there ARE things you can do to make it play better, and without compromising visuals.
On the spec in my sig, I'm running it at mostly High, with Textures, Terrain, Effects, and Anisotropic Filtering set to Ultra, and Depth of Field set to Med. I also have Async Compute On, in-game Vsync On, and Min and Max FPS both set to 60. I'm also able to set Resolution Scale to 1440p, or as close to it as possible, as the game's slider oddly doesn't allow you to land right on it.
Gameplay wise, this game is very fun to play, very immersive, and at times, very challenging.