Louise Young LY11, made for eye shadow blending, is a brush of unusual size. I didn't realize just how wide it is (nearly 1") until I got it. LY11 is twice the size of Louise Young's Super Blender brush, LY46, which isn't exactly the tiniest (though it does appear dwarfed next to the brushes in the comparison photos).
LY11 is a beautiful sable brush, firmly packed with a lot of soft hair. The thing is, that when it comes to blending, I much prefer fluffier brushes. The Paula Dorf one is an excellent example for a blending brush for a large area that does the work without pushing too much pigment and mangling your eye shadow application. If I were to use LY11 in the same way I'd end up with a botched makeup look. I also prefer Bobbi Brown's Eye Sweep brush for an all-over wash and even gentle blending.
So how can this Louise Young brush still be useful?
It is a good blending brush for a less delicate makeup application such as concealer, corrector or highlighter. I use the LY11 to clean up under the eyes and deposit small amounts of liquid or powder highlighter then blend it in. As such, the LY11's softness is a very good asset. It is a high-quality brush, after all, even if it looks like something you use to paint your baseboards.
Bottom Line: nice to have but not a staple.
Louise Young LY11 Eye Shadow Blending Brush (£35.00) is available from louiseyoungcosmetics.com. They're happy to ship anywhere in the world.