Hi Ben,
One day I brought home a harness and leash for Charlie (now 9mos. old) This was about a month ago. I just wanted to get him used to it so that I could take him out in front of the building in the summertime. He seems okay with it if I hold him in my arms and walk around with him (I have only walked up and down the hall with him since it is still so cold). When I tried to actually walk him, it was a different story. He just stood there and pulled the leash in the opposite direction from where I was. I guess he's trying to tell me that he will not be "walked". I'm still trying to get him used to it. I think it's a little late for me to teach him to walk on the leash, but hopefully I'll be able to take him for some fresh air in the summer, at least in my arms.
Anyway, my suggestion would be to give it a try and make sure he's completely comfortable before you attempt to take him out for a long time, like when you go camping. He may like it. Lots of people walk their cats on leashes. Good luck and let us know...