Especially if you use this song, you kind of have to sync the kills to the "boom". Its just asking for it. Safe more scenes and do more cuts in a video. Keep the cuts synced to the song beats. Result will be an easy but pretty cool montage without much know-how needed.
Otherwise cool vid. Those SPG hits were indeed impressive.
In the future I will do more cuts instead of longer clips, however before rendering it was better synced than after the render. I still have a long way to go but it's something to aim for.
The fact also is that when I record I often get a 10FPS drop, so on Sbeneh I often play then with 10FPS. So until I have a better rig I still have to do some occasional recording.