1. The product built quality is pretty good, doesn't feel like a cheap plastic product. 2. The four color cards provided does the job well. 3. The touch power on/off works good, you just need to place your finger at the marked symbol for less than two second and it will power on, repeat the same to power off. 4. You can increase the brightness just touching on the pad on the top, you can slide your finger from left to right or right to left to increase or decrease the brightness. 5. As for usability it will be very useful for photography; portable, decent weight, and rechargeable through USB. As described in the manual it takes around 50 minutes to fully charge and will last up-to 1 hour, the battery capacity is 800mAh. I have also provided the comparison image between the Lighter and the product you can checkout to understand the size. The product was delivered within two weeks, since it was a international shipping for me it was fast.