In Sweden a stopwatch is mandatory equipment for IFR certification of the aircraft. That is, it should be installed in the aircraft (yoke or panel). The ADF does not suffice as a timer.
Personally I like having the timer right in front of me, not over to the side where the ADF normally sits, your scan may not pick it up out there when the going gets tough.
I'm used to having a timer on the yoke, right where my approach chart is - works for me...