shuen, Franky: i think the difference is more in old/new, traditional/modern and nothern/southern terminology. if you check the old Southern gf manuals, you very seldom meet ma bou, gung bou, heui bou (= ma bu, gong bu, xu bu), but you see plenty of sei ping ma, ji ng ma, diu (geuk) ma. in the North, they use bou/bu, "step" for the stance, in the south ma, "horse". ma bou has a little different meaning in the South, it means generally "stances and footwork", not a specific stance. anyway, it gets all mixed up today, so it really does not matter, although i personally prefer the old, Southern way.
jau ma, nau/lau ma and tau ma is a different case, here it is really descrition how to get to the stance (called usually neui ji ma)
although we are stealing this topic, it is interesting, more food for though for my encyclopedy. althoug it is called A Conceise Encyclopedy of Hung Kyun, i want to be as complete and accurate as possible.
to the topic: vaulander, i admire your enthusiasm and hard work, but still, i strongly suggest to forget about DVDs, save the money and learn from a teacher. in the USA, you have so many choices, man! i wish you all the best in your training!
