Do you purchase multiples of the same light?

I have a few of each as well. The D4 is nice, but the KR4 is much nicer.

The only pair I have so far are Sofirn SP40s, one in Green, the other in Sand colour. Indeed affordability is the key to buying more than one of the same model. Each of these nice headlamps costs only S$30 or US$23. And each comes with a nice headband and a 18350 short tube.