Lights are not just about Lumens, You need to think about how the light is focused/dispersed on the trail, how the heat built up by running an LED at high currents is dispersed, the types of conditions the light is used in does it require a degree of waterproofing.
Most Chinese lights claim the Lumen output of the light based on the theoretical maximum for the LED in the light, this can never be achieved out with Lab conditions so is a pointless value. Higher priced lights will in general quote actual lumens or actual and theoretical.
There will be some thought into the driver used, for example the LED’s may be driven at 70,80,90% of their maximum to reduce heat but still provide excellent amounts of light. Other lights use smart controllers that reduce the drive current if the heat of the unit exceeds a pre set value to protect the light.
The design of the casing of Chinese lights rarely take into consideration cooling of the light often have poor quality control and the type of reflector/optic is often not the most effective for the type of LED in the light.
You then also need to think about the quality of battery and charger that will be used to power the light.
My opinion of Chinese lights is it is astonishing what they can pack into a bundle for price, take some of the specification with a pinch of salt and you could get a bright light for your money that will give you an idea if you like night riding or not.
You will eventually see the shortcomings of an cheap light and will then look to upgrade by which point you may feel the price is worth paying for a more expensive light.