If you always shoot only JPGs and no longer shoot RAW, the Philips might be OK.
I always shoot only RAW (and then convert to ProPhoto RGB 16-bit} so I want to be able to see, and work with, as much of the captured spectrum that I can — even if copies of some of the images may later be saved as sRGB JPGs for web site display.
I think I'd be less disruptive if the advice were concentrated on the OPs specific requirements, not the advisors personal requirements!
What you choose to do may not be what Colin needs.
I shoot raw, never shot anything else. Don't care for jpgs, all get deleted once they get used, I have no issue with a budget monitor($200) for the majority of useage.
But yes, I have an extended gamut(Samsung) screen that cost a bomb(for a non pro, a highly superfluous expense).
It's use is appreciated, but side by side, the difference is so trivial, having it now I see the 'folly' in having used those funds on something that I didn't really need.
To the OP. be weary of 4K screens. Make sure your hardware can support it properly.
i.e. is your graphics card(or chip) capable of that output? If so, be sure it's properly capable of it(i.e. at 60fps, not 30fps).
There are a few gotchas when it comes to hardware you should make yourself aware of.
Another thing to be mindful of with 4K, is software. Not all software devs have the brains to set their interfaces up for 4K(looking at you Nikon!)
Some do, others don't. CaptureNX-D was updated with 4K support a while back.
ViewNX-i took longer to update. Both totally unusable at 4K before their respective updates .. near impossible to see their 'microfonts', and click on the correct part of the tool!
Most software works properly, but some don't.
Not that long ago I had to research screens(again) for my son .. maybe 6 months ago.
Found at that time, a Samsung 28" U28E590D, was the best value for money. Not the cheapest, cost me Aud $500 .... which would work out to about 300 Euro or so.
The only thing I don't like about it is the very plasticky stand they used. For son, it's fine. He does graphic design/animation type stuff.
Screen quality when calibrated is top notch(very low deltaE, using BasicColor).
Compared to my $2.5K Samsung, you wouldn't notice any difference unless your workflow was all in 10bit(hardware). Even then, the difference is too minimal to justify the additional $2K expense.
These extended gamut screens that Ann refers too, are specialist stuff. Totally useless if your entire hardware isn't capable of 10bit hardware settings. Not all graphics cards have that ability, no on board graphics chip(that I know of) has.
So if you do decide 4K is something you want(for the future too), then be sure your hardware can support it properly.