Never let them eat too much. They will eat and eat if they're good eaters. They won't stop. Switch of the diet Cricket's mainly throwing some roaches and worms every now and then my adult males I try not to feed over 14 crickets. I use hornworms butterflies and superworms sometimes I get them...
To be honest you can hold them if you want 4 the ride or just the box he came in. I usually box and bag them but I have a few that just come right out and sit there.
I would not recommend traveling with him in a cage. Way too many things that could happen hour and a half is not that long for them to be boxed or bagged
Temperature has a big role in the hornworms. Lower the temperature the slower they grow when you're at about 80 they grow really fast. If you keep them at 50 it'll stop their growth
You can find a lot of it about human consumption not much about chameleons. But I have read a few articles on chameleon consumption. I'll try to find the links