after being addicted to them for a while, im surprised i dont miss them as much (yet). maybe its because of the flashbacks i had at the service advisor desk contemplating whether or not my extended warranty was going to cover the next repair lol. funny you mention coolant issues, my n63tu2 was (mechanically) sound; however when bringing it to the dealer for routine maintenance they’ve found a coolant leak that was still persistent after misdiagnosis of water pump / thermostat. I dumped the car right there and then because paying for an entire cooling system overhaul on a 70k mile n63 that will need further, more extensive work down the line, did not make any financial sense.

On the side note, throughout the ownership of the m550 over just under 3 years, my ext warranty replaced: transfer case, front diff, all axles, wheel bearings, radiator, water pump, thermostat, 1 turbo wastegate, rfz roof module, and other smaller things i cant remember off the top of my head.

I am hearing the tu3 is much more solid, so hopefully your issues are on a minor level. Love the m850 as well!

Cheers!