X-pens/ dog pens for rounding up the flock

[Blondiega1]

My grand duckies are soon going to be big enough to sort the hens from the drakes.
I'm considering a x-pen or dog pen to herd them into a small space so I can separate them out.
Thoughts?
Any other suggestions for separating them?

 

[animal paradise]

Any where there is a small space so you can catch them. Dog pen sounds fine

 

[Blondiega1]

Any where there is a small space so you can catch them. Dog pen sounds fine

Thx!