Can anyone describe the fundamental differences between the Inova x1 spotlight (£13.50), the Arc AAA (£16.00), the Arc AAA premium (£24.00), the CMG Task Light (£10.00) and the CMG infinity ultra task light (£13.00)

I can't see any major differences except fot the light level in some of the modules and the fact that the X1 doesn't seem to have a lanyard hole. What is the factor that makes the polpular Arc AAA premium £14.00 more expensive than the CMG task light?
Can anyone enlighten me?

*These prices are from Outdoor Supplies UK. I am in no way affiliated with this company.