I'm guessing that you can't let them roam free until a certain age, presumably because they need their vaccinations or whatnot?
They're all jabbed up, but until they've been done, they don't get to wander about. Also, they've not started their worming/flea treatments yet.
Are you going to let them be indoors/outdoors cat?
Outdoors, definitely. They're a pair of little hunters if ever I saw any and it would be awful not to let them roam free. It's fairly quiet and safe round here and I think they'll do well. We just have to get them used to going into the garden and coming back again!
Did they go all floppy and forget how to balance when you put the harnesses on? We used them for ours when they first went out and they absolutely refused to believe that it is possible to walk whilst wearing a harness
They didn't like them very much to start with, but curiosity got the better of them pretty soon and they were dragging us all over the garden...