I started this thread in a hope to find solution to improve the night-time visibility after doing research on my own in the markets of Islamabad and Rawalpindi. I found many solutions that requires tinkering with the electrical system of Suzuki GS150 and I was afraid that the local motorbike electrical experts might mess things up so I wanted something that is plug-n-play.
Thanks to the brothers who have shared their views and experiences and I'm highly obliged to them.
In the pursuit of increasing night time visibility, almost every bike-electrician told me to stay away from xenon lights (called tube in the local market) and nobody managed to conveniences me on the ground of facts and maths. Everyone said the this tube will ruin the headlight housing by making it darker, etc. (I used one xenon 12V/35W for over 2 months and nothing happened, details are as follows)
So, I decided to buy one of good quality (from AliExpress so it isn't available in local market with better quality) and installed in my bike. Here are the pictures.
https://goo.gl/l01vYc (xenon folder)
I used this xenon for over 2 months (75 days) without any issues whatsoever and nothing happened to headlight housing and I'm not sure why everyone said that it could cause problems. Anyways,
https://goo.gl/l01vYc (LED folder)
I then ordered this LED (12V / 24W / BA20D connector type) that was plug-n-play and the results are comparable to the LED in the first post.
Xenon costed me Rs. 107.
And this LED bulb costed me Rs. 465.
I bought both of the bulbs from AliExpress and they were not available in the local market.
People who have 70cc or Honda 125 bikes they can opt for the same LED bulb but with lower watts which are available on AliExpress.
Just one more thing that I've observed. The stock bulb of GS150 is also available on AliExpress and that bulb is super-super-cheap, even cheaper than I thought.