My honest opinion based on my warped thoughts:
1. Acrylics - Adv. easy clean-up and less toxicity.
- Disadv. not as much color selection, don't seem as 'durable'
2. Enamel - Adv. color selection and seem more durable and readily available.
- Disadv. sometimes messy and more difficult to clean up.
Truth is, I just have more enamels in my paint drawer, and am more used to using them. I'm sure if I was willing to 'switch' I'd get the hang of acrylics too, but I'm used to using what I've got.
I do have several acrylics, but for some reason, I don't use them near as much as the enamels. I used them quite a bit more when I lived in an apartment and didn't want to fume-out my room-mate. Now, I have a nice little corner in the basement where my family won't be 'bothered' by the enamel fumes.
M.