This one is a game changer , if you don't want to read the link this is the big pro's on the camera.
True 4k recording x 30fps and 1080p x 120 fps (outrageous) the old 3+ Black was only 15fps at 4k
1 Ghz processor , GoPro has always had the edge with it processing but just takes it way more forward.
Inbuilt stabilisation and noise reduction (that's huge)
Different Lens available (thank you)
Inbuilt playback screen (about time)
No sport cam can come anywhere near this , but before you run out and buy it , you will need a serious computer to edit these massive files. You can knock the settings back for normal filming and really for most punters the std 3 Black is all you need to make Sup Porn like DJ does. To watch a 4k film you will also need one of the new 4k TV's. Here's the link it's in shops in about a month. SurfFx has their order in I'm nothing to do with GoPro just a camera junkie
www.hugedomains.com/domain_profile.cfm?d=thefusejoplin&e=com