I have both the LS10 and the D50.
The advantage of the LS10: Windshields are supplied with the device and it is much smaller.
It runs on two AA batteries (4 on D50).
The internal microphones sound a little better on the D50, but only a little...
So, for making some test recordings for education, the LS10 is the choice.

I hope this is helpful.

Markus