4 is good. Everything else is just good to have in case you want to know how bad it was at the beginning, but they have their fair share of good songs.
Except Traveling. That cover was horrible.
OH, the Japanese release of the US version, Taiko no Tatsujin - Taiko Drum Master. That version has a few songs exclusive to it on console, like the ABC song, and Saitama2000, but that's also in 3, I think.
__________________
Brawl Friend Code: 4468-0647-9801 PM me if you've added me, but I have probably already added you beforehand.
| 
What other ps2 taiko games are good? 
