I have three dwarf gouramis (males) in my 10g and they love each other - like was mentioned above, they hang out all day and chase each other when they feel particularly feisty but nothing mean spirited. Go for it.
edit:
I should probably mention that I have three because I've heard that if you get a pair, the stronger one will harrass the weaker one, so you should get three to split up the attention/aggression. Although, since your tank isn't tiny, they may not figh with each other. Just make sure that they have places to "call their own" male gouramis are territorial and it will cut down on agression if they have their own space.