hallo!
For the past month, I’ve been watching the china release version of FP which in my opinion is pretty darn good, however I have been anticipating the HK version for quite some time, HOPING there will be added bits that will make the movie even better!
However that was NOT THE CASE!
This is the 2nd time I thought the Hk version was worse then the China version.
First it was SPL then it is FP.
SPOILERS! Here are the reasons:
The specials disc dvd can almost all be seen on Youtube. Which makes it pretty pointless almost, unless you are a collector of some sort.

As for the additional scenes, there are a few that were extended.
Ie. The first major confrontation / action scene was at a golf range. This particular scene always seem short to me, as if it was edited to make it more suitable for china audiences, and boy was I RIGHT!, there were at LEAST 5 seconds left out! The making of part on the special dvd and the youtube version has more action then this dvd, very very disappointing.

Another scene that was slightly extended was when a character was being smashed with a sledge hammer. The only difference between the versions is, you get to see a 2-3 more swipes of the hammer from far away, you barely see blood anywayz, I don’t know why they even bothered to cut it out.

This is probably the WORST part of the changes, which comes at the most crucial moment in the movies climax. After Both Donnie and Collin fell from the building, the mandarin version slowed it down and gave a moment to Collin and Donnie to intensify the final scene. It was an emotional one at that, and then Collin got up from the ground and gave Donnie one helluva menacing look and waved him to an area to fight their battle. – In the HK version, the WHOLE scene was taken away, and Donnie was the one who waved him over, which makes this for another Dragon Tiger Gate moment, where he waves the bad guy over to him. This causes the whole fight to look way too one sided again! I feel the emotional scene was so crucial to the movies ending, that I was actually disgusted and mad while watching the HK version tonight.

There must have been a few more things that were changed, I am sad to say I was so pissed I skipped through most of it.
IN CONCLUSION:
If you don’t care about the language,
BUY THE MANDARIN VERSION 
with Eng Subs. I personally don’t even know if they have one, try your best to find the China Version, because the Hk version is pretty bad compared to it.