I have had good luck raising a couple of katydid nymphs to adult. I don't know the species as I have had different ones. The hard part for me was finding a variety of food plants. I could only find 1 or 2 plant species that my katydids seemed to enjoy. <_<
I always released them when they became adult because I have never had both sexes at the same time.
They were very cool and I hope to raise more. One was so calm that she wouldn't fly away when I tried to release her, but she was a tiny nymph when I found her. More than 1 of them would just chill out and eat out of my hand.