Yep, there are some real high-mileage S's out there. Most of Amsterdam taxi's were S's last time I was there. They seem to be wearing well, and with little to service.
I'll be honest, the tech in the iPace is miles behind the Tesla. The GUI is slow and non-intuitive. In a weeks ownership I've noticed that the front windscreen is leaking somewhere or the coolant hoses are leaking (both common issues). There is a big battery issue where people can only charge to 70%, which luckily this one doesn't have. It's covered by the 8 year/100k mile battery warranty.
I picked this one up cheap (it would be cheapest in UK if I put in on Autotrader), so it will likely be 6 months free or at worst cheap motoring. The Tesla took 4 months to sell (mileage and time of year), and I expect this to take just as long, so it will be on Autotrader in 2 months :-)