Very few (none?).
Compared with a tuning fork Accutron though, the quartz ones aren't that smooth at all.
If you look at a number of automatic watches, you'll see that the actually tick 'sub-second' and that some tick faster than others, so seem smoother.
The quartz Precisionist movement simply ticks sub-second, which is unusual for a quartz movement, but I think it's true to say that the Smiths Seafire does too (and any watch that shares its movement, presumably).
The old tuning-fork electronic watches really seem to sweep completely smoothly, but I guess they just 'tick' faster than anything else.
M.