I owned an M37 for a year or so.
Found it great value, about half the price of the equivalent german car.
Engine was nice, gearbox not so much, had all of the features including radar cruise. I managed to sell it easily too because it was good value i thought it would stick around for a while but it was gone within a few weeks. Fuel consumption is poor.
Handling wise it was ok, nothing special.
I replaced a wheel bearing, some brake pads and a fan belt and maybe pulley.
Wheel bearing was easy from autodoc.
Brake pads were easy to get
Fan belt was hard to source, very expensive from infiniti and no data on the aftermarket. I ended up importing it from usa using rockauto, which you can use for other parts too. I think it was continental.
Anythkgn else ask away.