Thanks @BigDave I am extremely grateful for you taking the time to provide such a comprehensive reply. It’s all really helpful info although, as you rightly predict, our usage is very different!
The Air Suspension feedback is extremely interesting. It’s standard on the 50e (which I’m testing this week) but thankfully the M60i that I’m testing doesn’t have it as an optional extra, so I can see what the difference is like, as both have 22” wheels with standard tyres. There were several reasons that I fancied it. Firstly, I’m concerned that the M-Sport (and in particular M60i) suspension may be too firm. Secondly, all the reviews I’ve watched rave about it. Finally (and most importantly) as I have to hoist my wife in and out of the car (something that we can’t test) and I have to lift her wheelchair in and out of the boot, I figured that the ability to lower the car might be useful and make life a little easier.
As for the wheels, like you I’ve tended to steer away from huge wheels (20” is the biggest I’ve had) due to the greater risk of kerbing them, but the review comment about tyre noise with the run flats concerned me and to avoid them you have to jump to 22”. Annoyingly, neither test car has run flats but, as mentioned, I’ve had them on quite a few BMWs previously and never had an issue with them.
Unfortunately, as for the tech pack, our last two cars had Head-up display, and so I would miss it. I also regretted not getting Harmon Kardon on my last 2 BMWs. I agree that the extra parking stuff is superfluous. The Bowers & Wilkins system is an extra £3.5k over the Harman Kardon, which I’m just not prepared to pay, especially as a lot of my in car listening isn’t actually music!
Once again, sincere thanks. I’ve watched every review going and the 2 x 48 hour test drives will hopefully nail most of this for me, but first hand owner experience is always invaluable.