Lights

Keeping this specific to blinking versus non-blinking, assuming that we are talking about London cycling, where being able to light your way is not relevant, a blinking light (assuming at a street legal blink rate, an street legal intensity and size) is going to be more visible, and more noticeable, than a constant light (of equivalent intensity over a given surface area at discreet points in time).

If you want a backup light (which may well be overkill for your average London commute), having that light blinking will be more visible too.

Neither will help a car judge the distance to the cyclist, if all they can see is the light.

Hence my disclaimer.

Also my rear does the followning

• strobe - off for a week - strobe - off for a week - strobe.....
  or
  
• weaker outer ring - off - powerful focused inner LED - off - weaker difuse outer ring.....
  
  

Neither of which strike me as useful, outside of seducing female commuters with spontanous disco shows....and even that is less effective than I'd like. May have to go back to the High-Viz Peacock feathers.