Louise Young LY06 Super Blusher brush is probably the biggest and fluffiest blush brush I own. I did quite a few comparisons and at first thought the closest one to LY06 is Rouge Bunny Rouge 002 (though you can see below that the Louise Young brush has a rounder and fuller head). Eventually I realized that my old Eco Tools powder brush is actually the most similar, though the hair is longer and a bit floppier (and also completely synthetic). This should give you an idea about the way Louise Young LY06 feels and performs.
Louise Young LY06 is great for light and almost ethereal blushes that give a soft and natural all over flush. The brush's incredible softness and density allow very easy blending, diffusing and smoothing any obvious lines. It also picks a lot of product, so this is not the brush for scarily pigmented blushes, though I do pick it up to finish the blending of a monster such as Rouge de Chanel.
These last two photos compare my Louise Young blush brush to a classic blush brush that's on the small-medium size, Trish McEvoy 2B Sheer:
As you can see, the size and shape of LY06 make it suitable for various other face makeup tasks, such as bronzing and powdering. If you thought the LY07, Super Powder brush, was too big for you (it's an incredible finishing brush, though), this smaller Louise Young brush might be more up your alley. It's beautifully crafted from natural hair and wood, doesn't shed and feels luxuriously soft.
Bottom Line: highly recommended.
Louise Young LY06 Super Blusher Brush (£26.00) is available from louiseyoungcosmetics.com. They ship internationally.