I think it's great. I'm just a beginner and being able to adjust the size of the board and play with as many handicap stones as I want allows me to tailor the game to play against the computer at a level where I can learn.

I haven't used the network features at all. It seems that there are two servers, but the busy one requires subscription fees? This is independent of the Goban application though and thus irrelevant. The Goban application is beautiful and fun to play. The Open/Save/Quit structure could use a little streamlining, but its hardly worth mentioning.