Well i loved them in the original and haven't really gotten enough into Brotherhood's version yet so for now this is my answer. What i love about them is that there not you stereotypical anime villains they have depth to them. That's why there awesome. I think someone already made one like this but i made one for myself

I loved both, but the 2003 ones had more development and more complexities.

I get where your coming from actually. Lust was more developed in the original. But from what i hear Envy my favorite homuculus has more development in Brotherhood. I might change my answer after i finish the second series.

I was actually mostly referring to Lust lol since she's my favorite. :P

I loved both but I agree they're stories were more complex in the 03 version of the FMA series and I much preferred the '03 Sloth over the manga/brotherhood Sloth but I still loved both versions of the homunculus.

Definietly, they're much cooler and have a better plot. Frankly I thought they ruined them in the first anime. Envy was the only one who had a good background story.

I think brotherhoods homunculus is more badass and cooler.

Brotherhood's were more bad ass but i've decided the original homunculi were much more complex.