For longest service life - All the way to the floor and no slippage on the take-up.
In reality - Not always to the floor, and slippage.
The compromise will shorten the life of the clutch, but I wouldn't (and don't) stress over it. As a rule, for normal driving, my clutch hits the stop.
I have also heard some people freak about wear to the "throw-out bearing" when the clutch is pushed in (and held) at a traffic light. That is getting a bit anal!
In reality - Not always to the floor, and slippage.
The compromise will shorten the life of the clutch, but I wouldn't (and don't) stress over it. As a rule, for normal driving, my clutch hits the stop.
I have also heard some people freak about wear to the "throw-out bearing" when the clutch is pushed in (and held) at a traffic light. That is getting a bit anal!