What I want is to be able see better when riding at night. I'm also thinking about getting Trail Tech aux led light, but they're not cheap and I can only buy a pair... when I do, I will have to choose whether to use the aux led light on my Monster or on my TE630.
I see.
So, which one do you ride more (at night)?
Or, which one do you feel the need for “more light output” ?
It makes more sense, obviously, to do the work on the one you ride the most, or (if you ride both of them equally, ) the one that has weaker headlight.
Other things to consider.
When you ride at night, do you ride on the twisty back road a lot ? Or, more like high speed on the long straight highway type of thing?
I ride a motorcycle / drive a car a lot at night. Quite a bit of it includes back road, so I need “I can see better at side of the road” kind of set up.
And this is what happens late at night, on the twisty back road.
For high speed straight line only riding, you will need spot beam pattern that can illuminate far, far a head.
Do you get a lot of fog / rain in your area ?
If you have to ride through fog / rain often, stay away from any light bulb that has “blue tint filter”, which includes PIAA extreme white (or whatever they call ...), because you can not see well with those “pure white” light.
The reason is pretty simple. The higher frequency lights (shorter wave length lights, such as blue, purple) focus IN FRONT OF human’s eye’s focal plane. (on top of that, those bulbs usually put out less light than regular clear bulbs.)
With those “pure , extreme white” color that comes out from blue filter on the bulb, your eyes will have to work extra hard to see, yet you can not see the detail still. This is an safety issue.
Bright single headlight vs adding auxiliary lights
If your goal is to see and be seen better, “more lights” wins, hands down.
Auxiliary lights can also work as a great conspicuity lights. Triangle-light pattern works a lot better than giant blob of single white light.
So, I’d say, decide which bike you want do work on first, then, decide whether you want to work on the headlight + auxiliary lights, or just add auxiliary lights.
Hope that helps.