Ok so here's the deal.
Monitors are all about context. If you're coming from a 17" CRT then even a basic little 24" 1080p LCD will blow you away. I've slowly climbed the ladder going through this exact path, and am currently gaming on a 34" 1440p 100hz MSI curved jobbie which cost a pretty penny (£350, still fuck all in monitor terms tbh) but I absolutely love it. I've always said that no matter what you game on, no matter whether it's PC, console, or even a fucking calculator - you're always staring at your monitor, so get something good. Nothing more disappointing than seeing someone spend £1k+ on a fancy PC with a graphics card putting out a bajillion FPS on a monitor that looks like it belongs in a 90s post office. When it comes to gaming, the things you actually interact with are where you need to spend the most money. Controllers, keyboards, mice, monitor, headset, etc. These are the things you're in direct contact with every moment of every gaming session so make sure it's exactly what you want, and that you're happy with it. @phil bottle has pretty much reached the pinnacle of affordable stuff with his ROG monitor, going another step up from that is - and this is no exaggeration - an increase of about ten fold. Monitors are second only to GPUs when it comes to diminishing returns. The more you pay, the smaller the bells and whistles get.
4k is a waste of money. I've been in this game long enough to be able to tell you that 4k gaming on the ps5 won't be 4k. It'll be pre-rendered cut-scenes and any gameplay will either be massively reduced in quality, or it'll run at 5fps. It'll very likely chop down to 1080p, or 1440p if you're lucky. To reliably game in 4k on a PC, you're looking at double, or even triple the price of a PS5 for the graphics cards alone. And that's on the lower end of the scale. To get good FPS, you're looking at a pair of 2080 supers, which will cost you £1500, and then you need the rest of the hardware to feed them with enough juice and enough pixels to render. A good 4k gaming PC is easily north of £3k, and that's without monitor or peripherals. No console is coming close to that for a long, long time.
For refresh rates, 1ms is wasted on consoles. Unless you intend to go all competitive and use a keyboard and mouse, that 1ms will be cancelled out by using a controller anyway. To benefit from such short refresh rates, you really want a PC with keyboard and mouse.
That all being said...
I have a 32" 1440p monitor at home, it's a bit of a beast, it's by no stretch of the imagination a high-end monitor but it's still fantastic, @Plumbers Crack games on exactly the same one, maybe he'll pop in and give us his thoughts. In fact, it's this exact model. If you want it, it's yours for the price of postage and a few beer tokens in the FGFGFGFGFGFGFG to help @GazzaGarratt Dad with the site maintenance costs. Let me know.
If it's not your bag however and you just want something nice and new, then this is your daddy:
https://www.hotukdeals.com/deals/msi-32-quad-hd-144hz-1ms-va-curved-freesync-gaming-monitor-2020-ps33155-at-aoebay-with-code-3529362