More than a bit of a negative description in my experience. I've had about a dozen rescues and all have been good layers - both battery and free range. The fox protection is easy enough - I dug down and put concrete under my coop area and just doubled the locks - only lost one to a fox and that...
I got most of mine from here - https://www.bhwt.org.uk/ - but you do have to wait for a batch to need rescuing.
Also Raystede do them but are currently closed.