I just saw your post and totally get the panic! Being super paranoid about spending big money on tech that might have weird flickering or backlight issues, I was in the exact same spot last month. I spent like three days straight reading RTINGS and watching every Hardware Unboxed video I could find because I just wanted something super reliable that wouldnt fail on me right away. The LG 27GP95R-B 27-inch 4K UHD Nano IPS 144Hz is what I ended up getting and ngl its been amazing!! I chose this specific one because LG actually makes their own panels and their quality control is usually way better than some of the cheaper brands. It handles 4K at 120Hz like a champ and the colors are just fantastic. One thing you gotta make sure of is that the monitor supports VRR properly. VRR is basically like magic for the PS5... it stops the screen from tearing and makes everything feel so much smoother even if the game is struggling. Tbh the HDR on this one actually looks decent too, unlike some of the really dim ones. It feels like a safe bet which was my main goal. Definitely look at the comparison tool on RTINGS before you buy anything tho, it shows all the technical lag stats which really helped me feel better about the purchase!

In my experience testing different displays over the years, choosing a monitor for the PS5 requires focusing on HDMI 2.1 support above all else. You mentioned the Gigabyte M28U 28-inch 4K 144Hz, and your concerns about the HDR are valid. It is a budget-friendly option, but the peak brightness is kinda low for a true HDR experience. Honestly, it wont give you that wow factor you want for a new console. I have tried many setups and for your $650 budget, I would recommend looking at the LG 27GP95R-B 27-inch Ultragear 4K UHD. It is a very methodical choice because it offers the same high-end Nano IPS panel as more expensive models but cuts out the flashy stuff like rear lighting. It handles 4K at 120Hz perfectly via HDMI 2.1, which is exactly what the PS5 needs. Another strong contender is the Samsung Odyssey G7 S28AG70 28-inch 4K 144Hz. It often goes on sale and provides a very consistent experience without the weird glitches some older monitors have. I would avoid the Sony Inzone M9 for now tho... the blooming can be frustrating when you are just trying to enjoy a game. Stick with the LG or Samsung for a reliable, cost-effective long weekend of gaming.

This is exactly what I needed to hear. Youre a lifesaver honestly.