I've only ever used acrylics, but from what I've read, enamel should work fine too, I'd just avoid using any strong sealants or coats, just in case.
If memory serves me right from my time doing miniature models, enamel paints can be more liquid than acrylics (?) which means that the first coat may not look very sharp (then again, if you order it in red, it's less of a problem than it would be on white).
If you read through the base action figure description that's linked above in the description of this figure, there's a section about painting (and everything else), should help you understand what to expect and why.
I don't do the Kraylon coating at the end anymore (as described there) because I noticed that it doesn't need it... you can't scratch the paint after a month or so, with or without a finish coat applied. I apply some shiny coat here and there to make some details and materials pop against the skin texture, but that's all. Hope that helps, any other questions, feel free to ask :)