I like the idea of heras panels for doing batches of cockerels or pullets. Plus, you can always sell them on if you don't get on with them.
I struggle with netting although we still use it. This time of year it's getting blown about and with the ground so soggy, you have to keep moving the spikes. In the summer it's a bit of a nightmare to keep the grass from shorting it. Plus on uneven ground like ours is, it's really difficult to keep the net upright and the lower strands off the floor.
What I am considering for our older flock of mungrels is making up a big pen, maybe 50m x 50m with a combination of wooden posts at corners and maybe a few on the sides and then those plastic fencing stakes in between. Then use all 8 of the wire clips so that you get a close fence. I'm sure this would keep a fox out, it wouldn't need as much power as a net and would be easy to strim around if need be. Plus it would probably be cheaper than a net.