I've been a long time Melty Blood player. This Steam version is pretty much the defacto version. It is however missing the PS2 only Bamboo Forest stage with the KnK theme. That was missing from the original PC version too, but was hack-able back in. I hope a similar mod comes to the steam version. Since it is used in story mode, if memory serves me right, it should still be int he game, just locked out of stage select.
I would highly recommend this game if you like "anime" fighters, or high paced fighting games.