As an update, my experience of renting an EV in the UK was a mixed bag.
On the plus side I really liked the Polestar 2 as a car and could see it or a similar Tesla Model 3 as my daily driver. The acceleration is intoxicating and it is cathedral quiet on the motorway. Range was more than adequate at about 260 miles (420 km) and I think the economy was OKish (30 kWh per 100 miles).
Now the bad part, it is without doubt more expensive to run an EV in the UK if you do not have the benefit of home charging. The public charging network costs anywhere between 79 to 85p per kWh (DC charging). There isn't a price differential if you go for 50 kW or 150 kW (rapid).
So in summary if you're renting a car in the UK and plan to do a few long distance trips it is much cheaper to get a petrol or diesel vehicle. Its also less hassle since you don't have to factor in 20-30 min stops to recharge.
Good you noted the economy. My Model 3 used 171 watts/km over 4 years. Which is equivalent to 27.3 w/100 miles.
My Model Y uses 141W/km (22.6W/mile) in the summer and 153 (24.4) in the winter. The heat pump likely accounts for most of the improvement.
I have driven to the UK a couple of times in the Model 3 and France & Germany (and Switzerland) are a breeze for Tesla Supercharging, but the UK is sadly slow building up the network. I head for Dorset and it's a desert there.
I think the price is 67p/kWh in the UK at the present and 77p for non-Teslas.
How did you get on with chargers? The only time I tried to use non-Tesla ones was a disaster - requiring registering and downloading an app - and then the thing didn't work...
Not too bad, the Polestar uses Google maps as its UI with excellent integration so I could filter out all the high speed DC charge points. I usually use Shell Plus with the Hertz keyfob but the others I used allow you to swipe with a debit card so no need to download apps or register online.
The bigger issue is machines not delivering the full promised 150 KW. Sometimes they max out at 50 - 70 KW (with the car on 20% charge). All of this is indicative of a fairly nascent platform with too many plugs and charging standards. Obviously owning a Tesla and using their networks would make life a little simpler.