In my case, hairs in the beard area and toes are rooted deep, resisting the Tria treatment. However, the surface areas are relatively small compared with legs, and I could finish those areas within 5 mins. Before the Tria, I used to pluck those hairs. In 6 months, I no longer pluck, but occassionally shave a few resurgent hairs for effective laser treatment. I guess the hairs in the beard area so far have been treated more than 10 times.
The Tria recommends no to apply the device to facial area, but I tried it anyway as my skin is relatively insensitive to sun burn and hairs are black. Also, I do not have so many facial hairs. I noticed that most caucasian women have more facial hairs than me.
During the initial phase of treatment, I used the Tria once per week or once per month, and also it took longer time to complete an area. After resurgent hairs became thinner, it took less time to finish an area, and I used it less frequently.
For legs, initially I treated randomly the entire area whenever I have leisure time. Nowadays, I apply the Tria for the few noticeable hairs.
I guess the effectiveness of the Tria depends on the hair color and skin condition. In my case, I guess it was very effective.
Barbie~~