these are all ws2812 strips (the one filmed is 60 leds/m)
they're a bit more expensive
but wow, didn't know they were dumping the ws2811's at such prices
. might want to buy some of those too
Also a difficult decision is 5V or 12V strips. the 12V are easier for longer lengths as there is less current needed for the same amount of power. But after some googling, i'm pretty sure the 12V strips just group sets of 3 rgb leds together, so you no longer have control over individual leds, which kind of sucks and defeats the point of neopixels.
The current demand is a royal PITA with the 5V pixels however >_<. my current setup is 450 leds, which can have a peak power of near 150W, that's 30A >_<.... being able to use 12V pixels and get that down to 10A would of course be awesome. It kind of depends what you want to do with them.
Also, not sure if it's mentioned on this forum already, but neopixels actually need about 3.7-3.8V to fully turn on all colors. Above that voltage you don't see any difference. The rest is just disippated as heat by the voltage control on the pixel.