I have a handful of Sigma brushes that I've purchased individually, all of which I've been extremely impressed with, one of my all time favourites being the Synthetic Flat Top Kabuki F80, it's incredible for applying foundation! They are very comparable to MAC brushes, with the same quality only slightly cheaper and a much wider selection, including kits and sets too.
One of their newest sets is the Performance Eyes Kit* which consists of 8 professional brushes designed to allow the precise application of liquid, cream and powder products for detailed eye makeup. They are actually quite tiny compared to regular brushes, the blending E36 for example, is probably half the size of a usual blending brush! Some of these brushes are like no other I've seen before but I believe every single one has a worthy purpose!
Blending E36 - natural bristles blend powder products onto small eye areas
Shader Lid E56 - natural bristles control the application of product onto the eye lid
Shader Crease E47 - natural bristles apply products into the crease
Shader Inner Corner E46 - natural bristles apply highlight colours onto the inner corner of the eye
Tightline Liner E16 - Synthetic bristles press gel, cream or liquid products into the spaces between lashes
Waterline Liner E17 - Synthetic bristles apply cream or gel products into the waterline
Smudge E21 - Natural bristles smudge products into the upper and lower lash lines
Eye Liner E11 - Synthetic bristles apply gel or cream product to create a detailed liner look
My thoughts? It may seem pretty pricey at £49.95 but if you're into creating elaborate eye looks then I believe this kit is a must have, I wouldn't however, recommend it as a starter kit, there are actually plenty more sets on the Sigma site which would be more suitable if that's the case. I feel a gal can never have too many makeup brushes, especially when it comes to eyes, I have quite the obsession with blending brushes.. *le sigh*
What are your favourite eye brushes?