What is the best way to deal with very slow 2d motion?

Making Motion in AS3 is not hard, but to make a very very slow motion, I met a lot of troubles today.

Well, I have some stuff on my stage and I wanna move them very very slowly, using a “Timer”, then I have two ways to go. But both of them have disadvantages.

1) Make the interval as small as possible, and add 0.005 to sprite.x in each time handler;

Disadvantage:

I’m afraid Flash was working in a strange way since as2 when dealing with small float numbers, sometimes the x value of a sprite is even not changing when “[FONT=Courier New][COLOR=Navy]sprite.x += 0.005[/COLOR][/FONT]” is executed.

2) Add 1 to sprite.x in each time handler but make the interval much bigger.

Disadvantage:

To let the sprite move in a bigger interval could also slow it down, even save a lot of the CPU cost. But then the animation is performing very bad smoothing.

So is there anybody who has a better solution for this case? Maybe not using Timer? Anyway, thanks in advance!