From the top of the pic, you can see the facial and eye mask from Japan, followed by the MG brand facial mask (brand from korea, made in china) while the bottom section of masks are a collection of france, korea and taiwan.
When I feel stressed out or tired, just putting on a facial mask helps relax and refresh my skin. But finding the right mask can be both tedious and tricky. Everyone have different skin type as well as different qualities they are looking for, e.g. sebum/oil control, hydration, brightening, etc. Apart from the type of qualities you are looking for, there are also a lot of different ways to deliver these nutrients to your skin, e.g. jelly mask, mask sheet and cream mask.
It was infact during my trip to China that I got hooked onto sheet masks. I also learnt that they are many different types of sheet masks out there. Things to look for in choosing mask sheet are like:
1. Serum (e.g. purpose, amount, etc)
2. Type of sheet mask (e.g. paper, cotton, non-woven fabric, silk like texture)
3. Mask cutting (whether it can adhere well to the surface of the skin to deliver the maximal nutrients)
I have yet to try out all the mask that I collected. These are two of the mask that I tried so far.

Material : Cotton (Note: when using cotton sheet mask, do not exceed more than the advised time slot on the packaging, usually around 5-15 minutes)
Country of origin : Japan
Cutting : ☺ ☺ ☺ ☺
Serum : ☺ ☺ ☺
No immediate effect after first use and it contains slight amount of alcohol.
Material : Non-woven fabric
Country of origin : China
Cutting : ☺ ☺ ☺
Serum : ☺ ☺ ☺ ☺
The skin is noticeably hydrated and smooth on the next day. But it is slightly tricky to wrap the mask sheet around the face.

Hope this short review of mask sheet can help someone out there review what mask to try out. But one important point to remember when trying out mask sheet is to use a bit of the serum to test for any allergy prior to use. So, have fun with your mask~! =D