Advice - LED neon style chase light

Hi All
Sorry for this post but Im so confused with the LED scene that im overloaded.
Im trying to make a 5m LED strip (similar to LIFX neon flex) so a defuser to hide the individual leds that I can create a white chase light.
It will go up a flight of stairs (or down) and trigger on a movement sensor at each end of the stairs.
The amount of available leds on btf lighting is great but so confusing. Im not preferenced to 12 or 24v. I understand that quinled controllers are good but not committed to anything. I believe the more leds per meter the better quality but ??
Has anyone done this who could advise on what hardware they used.
Would be so gratefull
Thanks in advance…
peter