After reading almost unanimously positive reviews for this film, I thought I'd pick it up. I've also been practicing Wing Chun for ~7 years, so from that perspective, I was interested to watch the film.
To start, the Blu-Ray version seems to have some technical problems. Fast forwarding, accessing menus (there don't appear to be any) and other aberrant behavior made me wonder if I'd actually get to watch the film at all. I've never had problems with any other Blu-Ray film I've purchased.
As a result, I was not able to choose sub-title options, and had to make do with the dubbed English version, which makes it look/sound like one of those old 1970s Kung Fu movies.
While the action sequences are engrossing, the plot is tired, thin and predictable. Clearly, the Chinese still harbour deep resentment towards the Japanese for atrocities committed from 1935 onwards and this film trots out those old sterotypes a la Bruce Lee's "Chinese Connection". As soon as the characters are identified (e.g. Japanese general who happens to be karate master, sadistic Japanese colonel,etc.), you pretty much know how things are going to turn out. Interestingly enough, the actor who plays the Japanese general has strikingly Western features, so that might be additional real-world commentary from the film makers.
Spoiler alert: My next comments will give away some of the plot, but you probably figured it out already.
In terms of historical accuracy, I wouldn't treat this film as gospel. For instance, Ip Man never fought a martial arts tournament with a Japanese general. But hey, it's a Kung Fu movie, so all reality bets are off.