I was thinking to obtain this lens several time.
at first sight - I'm already have DA40 and DA70, and they are perfect.
at second sight - DA40 and DA70 not too fast, f/2.8 and f/2.4
I was trying it and this lens was very good, even close to perfect, but... I'm does not really need it.

I was in two minds long time, until my ten-year-old son started using his own (!) Pentax- K100 with DA-L18-55.
and then I noticed, than he using the 18-55 lens, he does not feel the composition, he is lazy to move himself and camera, instead that, he is just using the zoom.
He is glad to use only his-own things, so my 40 and 70mm lens not interest to him.

If I win DA 50/1.8, it will be his private lens, as his Pentax K-100D.

attached my photo, taken at October 2013.