A 10 gal. is plenty of room for 2 dwarfs, but I would not get 2 because the stronger one will likely pick on the weaker one. This is my experience, anyway. It's OK to have 1 dwarf or groups of 3 or more, but not 2. Also, the more similar they look, the better they will get along with each other. They will still nip at each other and "face off," but no harm will come of it as long as each can hold it's own. If one is noticeably smaller or a different color than the majority, it may get singled out and picked on. As far as health is concerned- Dwarfs are sometimes known to die for "no particular reason," and are said to be prone to fungal problems, but I think they are worth the trouble personally.
Also, the above information applies to Dwarf gouramis ONLY. Most other kinds of gouramis are very aggressive toward their own species, and you wouldn't want to keep more than 1 of them. Also, some may get too big for a 10 gallon, but dwarfs are fine.
You could also have 2 pearl gouramis in a 10. They are mild-mannered, but somewhat bigger than dwarfs, so if you have 2 pearls there won't be room for much else.