I LOVE IT. it definitely takes a few trial and errors to get the coverage you want and how far away, where you should hold it, etc. I bought mine in January (I think) and I still haven't run out of it. I don't use it everyday maybe 3 or 4 times a week.
I do maybe a 20 second application and it covers everything, the youtube vid says 30 second for light and a minute for full coverage but think you would look like you had paint on your face. The coverage is light to full depending on how long you apply it but it looks so natural. I would say it tries to a slightly dewy finish, its hard to describe, maybe like glowy but definitely not shiny. I would say that through the day if you are oily you would probably have to blot once. The great thing about it is it will last all day though.
I got mine off ebay for $80 from a UK seller and bought the shade OP-1. I am MAC NW20 NW15 and it is a tad too light. I probably wouldn't have payed full price for it but i will definitely by refills! Refills are $90 but that comes with 2 so its really like $45 each (you just have to buy them both at the same time).
I hope this helps and you can pm me if you have any more questions!