I can open the Set Time dialog by double-clicking a keyframe or the playhead.

If I want to move the keyframe/playhead to 1.5 seconds mark I would enter the numbers as above but this would not work for me since this would mean 1 seconds and 5 milliseconds, (same as 1.005 seconds). If I want to enter 1.5 seconds I have to enter 500 in the ms field.

I think it would be better if the last field was not actual milliseconds but instead the actual decimals of the value.