...Manual says I have to change spark plugs and adj valves @ 12000 kms. Are most people following those intervals or waiting a bit longer?....
As onewizard said - PDG idea to check your valves,AND
open them up to the MAX end of the specs while doing so (as they will take a long time to "tighten-up" ONCE at max clearance), and to replace your spark-plugs, EVEN THO' THEY WILL LOOK LIKE NEW WHEN YOU REMOVE THEM!
I have a car that uses VERY similar plugs. My wife complained that the car would "kick-OFF" from cruise control on some steep hills near Kelowna, so I bought a new set, removed the OLD ones and compared old vs new. They looked pretty much IDENTICAL, but after the change the car had WAY more power, and would now hold constant speed up hills in "cruise", so I NOW follow "Ma Kawi's" recommendations.
...How many kms / Miles should I expect out of brake pads?....
My Gen 1 ('08) w/ 82K miles on it, is STILL on the OEM rear pads, but I changed the fronts [AND the discs] at 59,573 miles.
OTOH - my Gen 3 ('15V650) w/ 63,914 kms is still on the OEM front pads, altho' when I needed to replace a rear tire in Anchorage in '16 they told me that my rear pads were "toast", and replaced them. I'm STILL not convinced that they were worn-out - I use the rear brakes on the '08 the same fashion as I use them on the '15, so MAYBE I was "done" by that dealer...