I use it with the 131 and 109: As the synthetic hair at the center of the 131 is ever so slightly longer (forming a oval shape), it allows to apply color in one stroke, with a stronger pigmentation in the center (from the hairline downward towards the apples), but soft enough to look natural and fresh. Then I blend the edges with a 109. Using this technique almost gives an ombre effect. I wouldn't use much highlighter with Magenta (and this technique) so it doesn't take away from the berry-licious beauty of this p/b.
I like this technique with berry shades, as a full on regular application might give you a fever-ish look. You really want to achieve more of an ombre effect.
I hope this helps.