I am conceding defeat at our bed - what appears to be possums have been decimating my broccoli and cauliflower plants and I have installed netting. It looks like overnight my plants escaped further damage, but I fear that the little critters will likely end up hitting someone else's bed - be warned!
The netting is not perfect and there are plenty of gaps, so I won't recommend the product, but I suspect whatever is eating everything is big enough that it was too much hassle for it to get in. Anyone wanting to use netting themselves, I would suggest a width of at least 2m and length of 5m assuming your plants are only around 50cm in height.
Some of the much earlier damage (it is way worse now)
Netting (luckily, they don't seem interested in the pak choi?)