To help clarify--since I am probably partly responsible for the firemane topic--FMA has the potential to be a good card, but
very format specific. Neither of you are wrong, but salmo's position is probably more correct, in the dark, the majority of times.
When FMA has been good for me, it was in both iterations of the penny cube--lower power, rampy, formats. In those formats, a 4/3 first strike flyer is a pretty dominating board presence, and not much can really challenge that. Due to the bounce land ramp, 10 mana is going to happen--basically guaranteed in a slower matchup, in a generally slower format--so she provides a form of very real inevitability for the decks running her. Eternal Dragon functions in much the same way--but an easy modern day analog to this function would be manlands in modern jund (or at least modern before it became an overly linear format dominated by aggro, aggro-combo, and combo). We have a matchup with a tremendous exchange of resources, and than when both decks are exhausted and in top deck mode, you get this recurring inevitability in the form of FMA, that will happily trade 1 for 1 with whatever the opposing decks remaining removal is, or abyss whatever remaining threats come down (first strike is huge). The life gain is perfect, because in those matchups, you've probably been beat up a bit, and the gradual life gain pulls you out of "death by random catastrophe" range. Thats how the card should be thought of, and shes superbly designed for that role, once her other--numerous--needs are met.
In the old penny cube, I considered cutting her multiple times for power level reasons, as a resolved firemane was virtually impossible for some decks to adequately answer. However, thats a niche fact pattern, for an overly needy card.
If you don't have ready sources of ramp, she is probably never going to be recurred, and if your format is condensed, or focused on mana efficiency--the way most contemporary formats are--the front end of FMA has the same game play problems plaguing her that this entire class of high CC, non-ETB creatures have that just want to get by on their body alone--they open you up to numerous lines of losing play against mana efficient interaction and the cheaper board presence we all push.
The art is killer though