I absolutely love this brush, specifically for blending, soft contouring, and outer-V work. However, I also think that blending is one of the most crucial elements of eyeshadow application, so YMMV.
It's a tapered blending brush, so it's more directional than a rounded/conventional blending brush and slightly more suitable for outer-V work. It also applies shadows softly and diffusely in the contour area and for blending. I've also used it to highlight the browbone to good effect.
I also love it for contouring the sides of the nose as it fits nicely on my face.
The quality of the brush cannot be understated -- it's sable after all. The price also cannot be understated -- it is expensive, period. However, [insert usual phrase about it being an investment, quality, long-lasting, etc.]. It's not an absolutely essential tool, but it is a very nice tool to add to your arsenal of makeup tools if you are so inclined to drop the money and are sufficiently invested in eye makeup application.
This is my favourite eye brush (along with Trish McEvoy #29). It's perfect for shadow application on the crease/outer V and blending. The bristles are extremely soft, yet resistant enough too guarantee a good shadow application (and not only blending). For example, Trish #29 is a blending brush, it's very soft and it's not that good for application, just for blending - Shu #8HR can do both application and blending because of its format and bristle type.
This is expensive but it's really worth it - I'm not very skilled but after getting these 2 brushes I mentioned, my eyeshadow application improved 10000x.
This is a very soft, handmade sable brush with an angle shape made for blending and contouring.. fits perfectly in the hollows around your eyes.. I also love how the handle is contoured to fit comfortably in your hand - it's not just straight up and down but wider at the top and gets narrower at the base. I'm sure I will be using and loving this for years and years. A definite recommend and repurchase!!
My ABSOLUTE FAVORITE eye brush...and trust me...I own a lot of them. This brush is absolutely perfect for contouring and blending, and is firm enough so that you can apply shadow with absolutely perfect control. (as light or as vibrant as you wish) Retails for $65, though I got a great deal on a large (19 piece) set of brushes, so this was absolutely worth it. Would definitely buy this brush again, though I really hope I never have to. (Considering buying a backup set of shu brushes just in case, they're just that good)