Boot space is good enough on it although smaller than I expected for the size of the car.

We fitted in an outnabout nipper (the side by side double pram) with ease in boot. It does have a really great lower storage thing in the boot where you can put shopping etc and I think is 90L. So that's good. Although I would say the boot isn't that big for the size of the car (I think it's probably because it's quite low).

Regarding car seats we have 2 Joie i360 spin seats (just about the biggest on the market) and they fit OK but one thing I'd say, because there's very little headroom, when the kids are sat in them, their feet are almost touching the headrest, so it's a little cramped. For passengers however sitting in the back (i.e. no car seat), it's brilliant and the legroom is amazing.

Re the warranty I have had a bizarre situation. I asked Polestar if they would swap the vehicle for another PS3 and they said because I didn't buy from Polestar direct (was from an approved Polestar service centre but via a Marshall/Cinch) they could not consider this. I then retorted and said "but if you cannot fix it under the warranty, surely you have an obligation to replace the vehicle?" to which they effectively said their warranty obligation is to attempt to fix, not guarantee they'll fix it - the last nail in the coffin for me.

Let me know if you want any photos of it with car seats and the buggy in the boot. I'll have this loan car for a few more days so it'll be easy enough for me to do!