It does have better PQ with Nano-IPS and brightness/contrast specs that qualify for HDR400 (not sure why they didn't certify that one). Also, the design of the LG is so much better than the AW and Predator. Perch it on an arm and it has no logos, which is downright amazing compared to the current trends. The sphere lighting actually looks like it will provide a decent ambient effect.
It all depends on what the user is looking for.
The design is certainly very nice, LG do have that down on many of their monitors. I do not believe Nano IPS has actually been tested properly or seen on a monitor in the wild yet to make any definitive statement on yet. It may offer something extra, but how much we can't really say at the moment. Regards HDR 400, it doesn't matter if it would qualify as the G-Sync module prevents it, so it will not receive an HDR signal.
Based on everything we know, there is little justification for a £400 premium over the alternatives. Of course some people will disagree... 'worth' is a subjective thing after all, but in view of the spec, the value just isn't there at £1200+.