i'll nip this in the bud right now. Their no no way in hell you're getting a console that'll do 4k60 for around £400. This isn't like current gen consoles, before they came out, we were already disappointed in the jaguar cores. We already know a year ahead that these are gonna equal a high end pc. Saying that, even high end pc's struggle with 4k60. So i wouldn't be too surprised if its only some games that'll run 4k60. The only price these can realistically(lets say they only release one console) sell these for will be £599(nobody will want to break the 600 mark).
To be fair, in-game engine videos always look better than the final product