The acrylics are just watered down. I've never tried the clear medium... wonder what the difference is.

Watered down, the acrylics behave almost like watercolor while still wet. I've started to use acrylics even for the ground layer washes on some occasions, particularly when it comes to brown hues... those seem clearer, less likely to get muddy than those done with watercolor.

I love acrylics; I think they're much easier to handle than gouache. (And I'm not even touching oil color; I'm just not patient enough for those.) I used to think that you can't get good hues with acrylics, but that may have been a problem of the brand I was using. I'm using Schmincke PRIMAcryl and Rembrandt colors now, they're very good.