I've bought the Sigma eyekit a few months ago, and thought it was time I reviewed them for you.
This review is about the Eye Liner Brush SS209, now also known as E05.
Info from the Sigma site:
An extra-fine tipped synthetic fiber brush that delivers a precise, firm, even stroke to line the eyes.
I really like this brush, and use it pretty much on a daily basis. It is pretty firm, which is why the pointy tip stays pointy after using it for some time, unlike cheaper brushes I've had.
As you can see below, this brush can be used for straight lines but also for more artistic uses. It's flexible enough to make curves, yet firm enough to make a perfect straight line.
I mostly use this below my eyes, especially on my inner eye corner. I also use it to apply eyeshadow below my whole eye.
This brush is not pricky and very easy to use. It can be bought for 9 dollars at the Sigmastore. It comes in an eyekit with 6 other brushes which costs, for example, 39 euros at Enchantra.