I was staying here while self-isolating prior to surgery and then while recovering afterwards, so I probably spent a lot more time in the flat than most guests would! It's very well-equipped. The kitchen has most things that you'll need: a fridge-freezer, utensils, oven, crockery etc. It's an induction hob, which took a bit of getting used to, but it was perfectly functional, and there's a kettle and toaster and so on. There wasn't a baking tray for use in the oven, which was mildly inconvenient, but there were saucepans and frying pans for the hob and there was a big casserole dish-type thing that worked for oven cooking in a pinch.
Supplies wise, there were teabags and a few bits and bobs in the cupboard (salt, olive oil etc), and there are a couple of Sainsbury's Locals within very easy reach for getting further supplies. There was also loo roll supplied, although we did need to supplement that too. There weren't any replacement binbags for the kitchen bin which was less ideal, but if you're only staying a short while and aren't cooking a lot, then that might not be that important. There are scourers and cloths and other cleaning supplies.
The WiFi was fine in the living room and kitchen -- I managed Zoom calls without many problems -- although it doesn't reach one of the bedrooms very well, so you probably wouldn't be streaming movies in bed. But, there's a smart TV in the living room with iPlayer and Netflix and stuff, so you'd not need to. The beds are comfy enough, as are the sofas (I spent a lot of time lying down). I will say that there aren't a lot of conveniently-located plug sockets in the bedrooms or the living room: I couldn't plug in my laptop and use it while sitting on the sofa, so an extension lead wouldn't have gone amiss.
The bathroom is fine and has shampoo, conditioner and hand soap supplied. The water pressure in the shower wasn't amazing, but I guess that's no huge hardship.
Being as how I was mostly stuck in the flat, I can't say much about the area, but it was very quiet -- minimal road noise or noise from people passing by, very peaceful.
The one problem I had was with check-in. The key is supposed to be in a lockbox which is halfway down the street, on a railing at floor-level next to a bin. Not the most auspicious start, and then the key was not IN the lockbox when I arrived as the cleaner still had it. So I was stuck on the doorstep in freezing temperatures (it was literally snowing that day) until somebody could get a key to me, which I didn't love. And returning the key to the lockbox at the end of the trip also didn't entirely go to plan as it was jammed and wouldn't lock properly, almost making us late for our train. Plus, it being so far from the apartment makes it less than convenient if you've got a bunch of suitcases to drag around, so I definitely thought that part of the arrangement wasn't ideal.
Otherwise, though, it's a nice apartment and provided a comfy place to recover from surgery.