Is Shibashi Tai Chi good for fitness and health?

Make sure that you learn at least some basics of Tai Chi or Qigong and not from a book, video or via internet. When doing Tai Chi or Qigong your body does a lot more than just moving the arms up and down and breathing in and out. Tension and relaxation (yin and yang if you want) at the same time in different parts of the body play partly a role. This is internal stuff and therefore not readily visible. If you simply moves your arms up and down and breathe in and out you are not doing either Tai Chi or Qigong and therefore will not reap the benefits you hope to get. These are things you definitely can not just simply learn from a video or in a matter of months in my opinion but some basic training will at least yield you some idea of what you are supposed to do when doing the exercises. Also make sure you find someone who can actually teach this. There are too many teachers out there who simply teach raising your arms and breathing in and out and do not understand much beyond this.