I really want the 4 channel emerald. Can you post more videos of different settings? Also what is the difference between the two 4 channel emerald drivers? Which one is the best to get?
For which is best of the two 4-channels... that really comes down to opinion and what you want.
Lots of people like the bright flash and flicker you can get with mixing White (sliver) into your blade colour of choice.
In more general terms; RGBW makes for easy 'cold' or pale colours, and RGBA makes for good warm colours.
It could be argued that if you really want yellow/orange colours RGBA is a better option because you can make some of those colours simply by adjusting the level of one die instead of two - which also means you're not drawing as much from the battery.