I'm certainly not an expert on the matter, but I own both Sanwa and Seimitsu joysticks and they play like a dream. Picking out the "ultimate" joystick is impossible as what you define as a good stick heavily depends on your personal preferences. I know that many people into VS-beatemups and shmups use the aforementioned brands as they play very smoothly (the Sanwas even more so than the Semitsus); also, most of these games were made by the Japanese, and in Japanese arcades the candy cabs either have Sanwa or Seimitsu parts (Sanwas mostly). Arcade authenticity and everything...
As I said before, I love them, but I've never tried out much else, e.g. Happs or whatever.